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Project: http://git-wip-us.apache.org/repos/asf/cassandra/repo Commit: http://git-wip-us.apache.org/repos/asf/cassandra/commit/7dfb25e3 Tree: http://git-wip-us.apache.org/repos/asf/cassandra/tree/7dfb25e3 Diff: http://git-wip-us.apache.org/repos/asf/cassandra/diff/7dfb25e3 Branch: refs/heads/trunk Commit: 7dfb25e3c29c46c5ba58c63613c8cc3b4ca28412 Parents: 54f7335 Author: Sylvain Lebresne <sylv...@datastax.com> Authored: Wed Jun 22 10:06:09 2016 +0200 Committer: Sylvain Lebresne <sylv...@datastax.com> Committed: Wed Jun 22 10:06:09 2016 +0200 ---------------------------------------------------------------------- doc/Makefile | 6 +- .../configuration/cassandra_config_file.rst | 1699 ------------------ 2 files changed, 5 insertions(+), 1700 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/cassandra/blob/7dfb25e3/doc/Makefile ---------------------------------------------------------------------- diff --git a/doc/Makefile b/doc/Makefile index 14e4c7a..9a736cc 100644 --- a/doc/Makefile +++ b/doc/Makefile @@ -14,7 +14,10 @@ ALLSPHINXOPTS = -d $(BUILDDIR)/doctrees $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) sou # the i18n builder cannot share the environment and doctrees with the others I18NSPHINXOPTS = $(PAPEROPT_$(PAPER)) $(SPHINXOPTS) source -MAKE_CASSANDRA_YAML = python convert_yaml_to_rst.py ../conf/cassandra.yaml source/configuration/cassandra_config_file.rst +YAML_DOC_INPUT=../conf/cassandra.yaml +YAML_DOC_OUTPUT=source/configuration/cassandra_config_file.rst + +MAKE_CASSANDRA_YAML = python convert_yaml_to_rst.py $(YAML_DOC_INPUT) $(YAML_DOC_OUTPUT) .PHONY: help help: @@ -49,6 +52,7 @@ help: .PHONY: clean clean: rm -rf $(BUILDDIR)/* + rm $(YAML_DOC_OUTPUT) .PHONY: html html: http://git-wip-us.apache.org/repos/asf/cassandra/blob/7dfb25e3/doc/source/configuration/cassandra_config_file.rst ---------------------------------------------------------------------- diff --git a/doc/source/configuration/cassandra_config_file.rst b/doc/source/configuration/cassandra_config_file.rst deleted file mode 100644 index b7d1bbc..0000000 --- a/doc/source/configuration/cassandra_config_file.rst +++ /dev/null @@ -1,1699 +0,0 @@ -Cassandra Configuration File -===================== - -``cluster_name`` ----------------- -The name of the cluster. This is mainly used to prevent machines in -one logical cluster from joining another. - -*Default Value:* 'Test Cluster' - -``num_tokens`` --------------- - -This defines the number of tokens randomly assigned to this node on the ring -The more tokens, relative to other nodes, the larger the proportion of data -that this node will store. You probably want all nodes to have the same number -of tokens assuming they have equal hardware capability. - -If you leave this unspecified, Cassandra will use the default of 1 token for legacy compatibility, -and will use the initial_token as described below. - -Specifying initial_token will override this setting on the node's initial start, -on subsequent starts, this setting will apply even if initial token is set. - -If you already have a cluster with 1 token per node, and wish to migrate to -multiple tokens per node, see http://wiki.apache.org/cassandra/Operations - -*Default Value:* 256 - -``allocate_tokens_for_keyspace`` --------------------------------- -*This option is commented out by default.* - -Triggers automatic allocation of num_tokens tokens for this node. The allocation -algorithm attempts to choose tokens in a way that optimizes replicated load over -the nodes in the datacenter for the replication strategy used by the specified -keyspace. - -The load assigned to each node will be close to proportional to its number of -vnodes. - -Only supported with the Murmur3Partitioner. - -*Default Value:* KEYSPACE - -``initial_token`` ------------------ -*This option is commented out by default.* - -initial_token allows you to specify tokens manually. While you can use it with -vnodes (num_tokens > 1, above) -- in which case you should provide a -comma-separated list -- it's primarily used when adding nodes to legacy clusters -that do not have vnodes enabled. - -``hinted_handoff_enabled`` --------------------------- - -See http://wiki.apache.org/cassandra/HintedHandoff -May either be "true" or "false" to enable globally - -*Default Value:* true - -``hinted_handoff_disabled_datacenters`` ---------------------------------------- -*This option is commented out by default.* - -When hinted_handoff_enabled is true, a black list of data centers that will not -perform hinted handoff - -*Default Value (complex option)*:: - - # - DC1 - # - DC2 - -``max_hint_window_in_ms`` -------------------------- -this defines the maximum amount of time a dead host will have hints -generated. After it has been dead this long, new hints for it will not be -created until it has been seen alive and gone down again. - -*Default Value:* 10800000 # 3 hours - -``hinted_handoff_throttle_in_kb`` ---------------------------------- - -Maximum throttle in KBs per second, per delivery thread. This will be -reduced proportionally to the number of nodes in the cluster. (If there -are two nodes in the cluster, each delivery thread will use the maximum -rate; if there are three, each will throttle to half of the maximum, -since we expect two nodes to be delivering hints simultaneously.) - -*Default Value:* 1024 - -``max_hints_delivery_threads`` ------------------------------- - -Number of threads with which to deliver hints; -Consider increasing this number when you have multi-dc deployments, since -cross-dc handoff tends to be slower - -*Default Value:* 2 - -``hints_directory`` -------------------- -*This option is commented out by default.* - -Directory where Cassandra should store hints. -If not set, the default directory is $CASSANDRA_HOME/data/hints. - -*Default Value:* /var/lib/cassandra/hints - -``hints_flush_period_in_ms`` ----------------------------- - -How often hints should be flushed from the internal buffers to disk. -Will *not* trigger fsync. - -*Default Value:* 10000 - -``max_hints_file_size_in_mb`` ------------------------------ - -Maximum size for a single hints file, in megabytes. - -*Default Value:* 128 - -``hints_compression`` ---------------------- -*This option is commented out by default.* - -Compression to apply to the hint files. If omitted, hints files -will be written uncompressed. LZ4, Snappy, and Deflate compressors -are supported. - -*Default Value (complex option)*:: - - # - class_name: LZ4Compressor - # parameters: - # - - -``batchlog_replay_throttle_in_kb`` ----------------------------------- -Maximum throttle in KBs per second, total. This will be -reduced proportionally to the number of nodes in the cluster. - -*Default Value:* 1024 - -``authenticator`` ------------------ - -Authentication backend, implementing IAuthenticator; used to identify users -Out of the box, Cassandra provides org.apache.cassandra.auth.{AllowAllAuthenticator, -PasswordAuthenticator}. - -- AllowAllAuthenticator performs no checks - set it to disable authentication. -- PasswordAuthenticator relies on username/password pairs to authenticate - users. It keeps usernames and hashed passwords in system_auth.credentials table. - Please increase system_auth keyspace replication factor if you use this authenticator. - If using PasswordAuthenticator, CassandraRoleManager must also be used (see below) - -*Default Value:* AllowAllAuthenticator - -``authorizer`` --------------- - -Authorization backend, implementing IAuthorizer; used to limit access/provide permissions -Out of the box, Cassandra provides org.apache.cassandra.auth.{AllowAllAuthorizer, -CassandraAuthorizer}. - -- AllowAllAuthorizer allows any action to any user - set it to disable authorization. -- CassandraAuthorizer stores permissions in system_auth.permissions table. Please - increase system_auth keyspace replication factor if you use this authorizer. - -*Default Value:* AllowAllAuthorizer - -``role_manager`` ----------------- - -Part of the Authentication & Authorization backend, implementing IRoleManager; used -to maintain grants and memberships between roles. -Out of the box, Cassandra provides org.apache.cassandra.auth.CassandraRoleManager, -which stores role information in the system_auth keyspace. Most functions of the -IRoleManager require an authenticated login, so unless the configured IAuthenticator -actually implements authentication, most of this functionality will be unavailable. - -- CassandraRoleManager stores role data in the system_auth keyspace. Please - increase system_auth keyspace replication factor if you use this role manager. - -*Default Value:* CassandraRoleManager - -``roles_validity_in_ms`` ------------------------- - -Validity period for roles cache (fetching granted roles can be an expensive -operation depending on the role manager, CassandraRoleManager is one example) -Granted roles are cached for authenticated sessions in AuthenticatedUser and -after the period specified here, become eligible for (async) reload. -Defaults to 2000, set to 0 to disable caching entirely. -Will be disabled automatically for AllowAllAuthenticator. - -*Default Value:* 2000 - -``roles_update_interval_in_ms`` -------------------------------- -*This option is commented out by default.* - -Refresh interval for roles cache (if enabled). -After this interval, cache entries become eligible for refresh. Upon next -access, an async reload is scheduled and the old value returned until it -completes. If roles_validity_in_ms is non-zero, then this must be -also. -Defaults to the same value as roles_validity_in_ms. - -*Default Value:* 2000 - -``permissions_validity_in_ms`` ------------------------------- - -Validity period for permissions cache (fetching permissions can be an -expensive operation depending on the authorizer, CassandraAuthorizer is -one example). Defaults to 2000, set to 0 to disable. -Will be disabled automatically for AllowAllAuthorizer. - -*Default Value:* 2000 - -``permissions_update_interval_in_ms`` -------------------------------------- -*This option is commented out by default.* - -Refresh interval for permissions cache (if enabled). -After this interval, cache entries become eligible for refresh. Upon next -access, an async reload is scheduled and the old value returned until it -completes. If permissions_validity_in_ms is non-zero, then this must be -also. -Defaults to the same value as permissions_validity_in_ms. - -*Default Value:* 2000 - -``credentials_validity_in_ms`` ------------------------------- - -Validity period for credentials cache. This cache is tightly coupled to -the provided PasswordAuthenticator implementation of IAuthenticator. If -another IAuthenticator implementation is configured, this cache will not -be automatically used and so the following settings will have no effect. -Please note, credentials are cached in their encrypted form, so while -activating this cache may reduce the number of queries made to the -underlying table, it may not bring a significant reduction in the -latency of individual authentication attempts. -Defaults to 2000, set to 0 to disable credentials caching. - -*Default Value:* 2000 - -``credentials_update_interval_in_ms`` -------------------------------------- -*This option is commented out by default.* - -Refresh interval for credentials cache (if enabled). -After this interval, cache entries become eligible for refresh. Upon next -access, an async reload is scheduled and the old value returned until it -completes. If credentials_validity_in_ms is non-zero, then this must be -also. -Defaults to the same value as credentials_validity_in_ms. - -*Default Value:* 2000 - -``partitioner`` ---------------- - -The partitioner is responsible for distributing groups of rows (by -partition key) across nodes in the cluster. You should leave this -alone for new clusters. The partitioner can NOT be changed without -reloading all data, so when upgrading you should set this to the -same partitioner you were already using. - -Besides Murmur3Partitioner, partitioners included for backwards -compatibility include RandomPartitioner, ByteOrderedPartitioner, and -OrderPreservingPartitioner. - - -*Default Value:* org.apache.cassandra.dht.Murmur3Partitioner - -``data_file_directories`` -------------------------- -*This option is commented out by default.* - -Directories where Cassandra should store data on disk. Cassandra -will spread data evenly across them, subject to the granularity of -the configured compaction strategy. -If not set, the default directory is $CASSANDRA_HOME/data/data. - -*Default Value (complex option)*:: - - # - /var/lib/cassandra/data - -``commitlog_directory`` ------------------------ -*This option is commented out by default.* -commit log. when running on magnetic HDD, this should be a -separate spindle than the data directories. -If not set, the default directory is $CASSANDRA_HOME/data/commitlog. - -*Default Value:* /var/lib/cassandra/commitlog - -``disk_failure_policy`` ------------------------ - -Policy for data disk failures: - -die - shut down gossip and client transports and kill the JVM for any fs errors or - single-sstable errors, so the node can be replaced. - -stop_paranoid - shut down gossip and client transports even for single-sstable errors, - kill the JVM for errors during startup. - -stop - shut down gossip and client transports, leaving the node effectively dead, but - can still be inspected via JMX, kill the JVM for errors during startup. - -best_effort - stop using the failed disk and respond to requests based on - remaining available sstables. This means you WILL see obsolete - data at CL.ONE! - -ignore - ignore fatal errors and let requests fail, as in pre-1.2 Cassandra - -*Default Value:* stop - -``commit_failure_policy`` -------------------------- - -Policy for commit disk failures: - -die - shut down gossip and Thrift and kill the JVM, so the node can be replaced. - -stop - shut down gossip and Thrift, leaving the node effectively dead, but - can still be inspected via JMX. - -stop_commit - shutdown the commit log, letting writes collect but - continuing to service reads, as in pre-2.0.5 Cassandra - -ignore - ignore fatal errors and let the batches fail - -*Default Value:* stop - -``prepared_statements_cache_size_mb`` -------------------------------------- - -Maximum size of the native protocol prepared statement cache - -Valid values are either "auto" (omitting the value) or a value greater 0. - -Note that specifying a too large value will result in long running GCs and possbily -out-of-memory errors. Keep the value at a small fraction of the heap. - -If you constantly see "prepared statements discarded in the last minute because -cache limit reached" messages, the first step is to investigate the root cause -of these messages and check whether prepared statements are used correctly - -i.e. use bind markers for variable parts. - -Do only change the default value, if you really have more prepared statements than -fit in the cache. In most cases it is not neccessary to change this value. -Constantly re-preparing statements is a performance penalty. - -Default value ("auto") is 1/256th of the heap or 10MB, whichever is greater - -``thrift_prepared_statements_cache_size_mb`` --------------------------------------------- - -Maximum size of the Thrift prepared statement cache - -If you do not use Thrift at all, it is safe to leave this value at "auto". - -See description of 'prepared_statements_cache_size_mb' above for more information. - -Default value ("auto") is 1/256th of the heap or 10MB, whichever is greater - -``key_cache_size_in_mb`` ------------------------- - -Maximum size of the key cache in memory. - -Each key cache hit saves 1 seek and each row cache hit saves 2 seeks at the -minimum, sometimes more. The key cache is fairly tiny for the amount of -time it saves, so it's worthwhile to use it at large numbers. -The row cache saves even more time, but must contain the entire row, -so it is extremely space-intensive. It's best to only use the -row cache if you have hot rows or static rows. - -NOTE: if you reduce the size, you may not get you hottest keys loaded on startup. - -Default value is empty to make it "auto" (min(5% of Heap (in MB), 100MB)). Set to 0 to disable key cache. - -``key_cache_save_period`` -------------------------- - -Duration in seconds after which Cassandra should -save the key cache. Caches are saved to saved_caches_directory as -specified in this configuration file. - -Saved caches greatly improve cold-start speeds, and is relatively cheap in -terms of I/O for the key cache. Row cache saving is much more expensive and -has limited use. - -Default is 14400 or 4 hours. - -*Default Value:* 14400 - -``key_cache_keys_to_save`` --------------------------- -*This option is commented out by default.* - -Number of keys from the key cache to save -Disabled by default, meaning all keys are going to be saved - -*Default Value:* 100 - -``row_cache_class_name`` ------------------------- -*This option is commented out by default.* - -Row cache implementation class name. Available implementations: - -org.apache.cassandra.cache.OHCProvider - Fully off-heap row cache implementation (default). - -org.apache.cassandra.cache.SerializingCacheProvider - This is the row cache implementation availabile - in previous releases of Cassandra. - -*Default Value:* org.apache.cassandra.cache.OHCProvider - -``row_cache_size_in_mb`` ------------------------- - -Maximum size of the row cache in memory. -Please note that OHC cache implementation requires some additional off-heap memory to manage -the map structures and some in-flight memory during operations before/after cache entries can be -accounted against the cache capacity. This overhead is usually small compared to the whole capacity. -Do not specify more memory that the system can afford in the worst usual situation and leave some -headroom for OS block level cache. Do never allow your system to swap. - -Default value is 0, to disable row caching. - -*Default Value:* 0 - -``row_cache_save_period`` -------------------------- - -Duration in seconds after which Cassandra should save the row cache. -Caches are saved to saved_caches_directory as specified in this configuration file. - -Saved caches greatly improve cold-start speeds, and is relatively cheap in -terms of I/O for the key cache. Row cache saving is much more expensive and -has limited use. - -Default is 0 to disable saving the row cache. - -*Default Value:* 0 - -``row_cache_keys_to_save`` --------------------------- -*This option is commented out by default.* - -Number of keys from the row cache to save. -Specify 0 (which is the default), meaning all keys are going to be saved - -*Default Value:* 100 - -``counter_cache_size_in_mb`` ----------------------------- - -Maximum size of the counter cache in memory. - -Counter cache helps to reduce counter locks' contention for hot counter cells. -In case of RF = 1 a counter cache hit will cause Cassandra to skip the read before -write entirely. With RF > 1 a counter cache hit will still help to reduce the duration -of the lock hold, helping with hot counter cell updates, but will not allow skipping -the read entirely. Only the local (clock, count) tuple of a counter cell is kept -in memory, not the whole counter, so it's relatively cheap. - -NOTE: if you reduce the size, you may not get you hottest keys loaded on startup. - -Default value is empty to make it "auto" (min(2.5% of Heap (in MB), 50MB)). Set to 0 to disable counter cache. -NOTE: if you perform counter deletes and rely on low gcgs, you should disable the counter cache. - -``counter_cache_save_period`` ------------------------------ - -Duration in seconds after which Cassandra should -save the counter cache (keys only). Caches are saved to saved_caches_directory as -specified in this configuration file. - -Default is 7200 or 2 hours. - -*Default Value:* 7200 - -``counter_cache_keys_to_save`` ------------------------------- -*This option is commented out by default.* - -Number of keys from the counter cache to save -Disabled by default, meaning all keys are going to be saved - -*Default Value:* 100 - -``saved_caches_directory`` --------------------------- -*This option is commented out by default.* - -saved caches -If not set, the default directory is $CASSANDRA_HOME/data/saved_caches. - -*Default Value:* /var/lib/cassandra/saved_caches - -``commitlog_sync`` ------------------- -*This option is commented out by default.* - -commitlog_sync may be either "periodic" or "batch." - -When in batch mode, Cassandra won't ack writes until the commit log -has been fsynced to disk. It will wait -commitlog_sync_batch_window_in_ms milliseconds between fsyncs. -This window should be kept short because the writer threads will -be unable to do extra work while waiting. (You may need to increase -concurrent_writes for the same reason.) - - -*Default Value:* batch - -``commitlog_sync_batch_window_in_ms`` -------------------------------------- -*This option is commented out by default.* - -*Default Value:* 2 - -``commitlog_sync`` ------------------- - -the other option is "periodic" where writes may be acked immediately -and the CommitLog is simply synced every commitlog_sync_period_in_ms -milliseconds. - -*Default Value:* periodic - -``commitlog_sync_period_in_ms`` -------------------------------- - -*Default Value:* 10000 - -``commitlog_segment_size_in_mb`` --------------------------------- - -The size of the individual commitlog file segments. A commitlog -segment may be archived, deleted, or recycled once all the data -in it (potentially from each columnfamily in the system) has been -flushed to sstables. - -The default size is 32, which is almost always fine, but if you are -archiving commitlog segments (see commitlog_archiving.properties), -then you probably want a finer granularity of archiving; 8 or 16 MB -is reasonable. -Max mutation size is also configurable via max_mutation_size_in_kb setting in -cassandra.yaml. The default is half the size commitlog_segment_size_in_mb * 1024. - -NOTE: If max_mutation_size_in_kb is set explicitly then commitlog_segment_size_in_mb must -be set to at least twice the size of max_mutation_size_in_kb / 1024 - - -*Default Value:* 32 - -``commitlog_compression`` -------------------------- -*This option is commented out by default.* - -Compression to apply to the commit log. If omitted, the commit log -will be written uncompressed. LZ4, Snappy, and Deflate compressors -are supported. - -*Default Value (complex option)*:: - - # - class_name: LZ4Compressor - # parameters: - # - - -``seed_provider`` ------------------ -any class that implements the SeedProvider interface and has a -constructor that takes a Map<String, String> of parameters will do. - -*Default Value (complex option)*:: - - # Addresses of hosts that are deemed contact points. - # Cassandra nodes use this list of hosts to find each other and learn - # the topology of the ring. You must change this if you are running - # multiple nodes! - - class_name: org.apache.cassandra.locator.SimpleSeedProvider - parameters: - # seeds is actually a comma-delimited list of addresses. - # Ex: "<ip1>,<ip2>,<ip3>" - - seeds: "127.0.0.1" - -``concurrent_reads`` --------------------- -For workloads with more data than can fit in memory, Cassandra's -bottleneck will be reads that need to fetch data from -disk. "concurrent_reads" should be set to (16 * number_of_drives) in -order to allow the operations to enqueue low enough in the stack -that the OS and drives can reorder them. Same applies to -"concurrent_counter_writes", since counter writes read the current -values before incrementing and writing them back. - -On the other hand, since writes are almost never IO bound, the ideal -number of "concurrent_writes" is dependent on the number of cores in -your system; (8 * number_of_cores) is a good rule of thumb. - -*Default Value:* 32 - -``concurrent_writes`` ---------------------- - -*Default Value:* 32 - -``concurrent_counter_writes`` ------------------------------ - -*Default Value:* 32 - -``concurrent_materialized_view_writes`` ---------------------------------------- - -For materialized view writes, as there is a read involved, so this should -be limited by the less of concurrent reads or concurrent writes. - -*Default Value:* 32 - -``file_cache_size_in_mb`` -------------------------- -*This option is commented out by default.* - -Maximum memory to use for sstable chunk cache and buffer pooling. -32MB of this are reserved for pooling buffers, the rest is used as an -cache that holds uncompressed sstable chunks. -Defaults to the smaller of 1/4 of heap or 512MB. This pool is allocated off-heap, -so is in addition to the memory allocated for heap. The cache also has on-heap -overhead which is roughly 128 bytes per chunk (i.e. 0.2% of the reserved size -if the default 64k chunk size is used). -Memory is only allocated when needed. - -*Default Value:* 512 - -``buffer_pool_use_heap_if_exhausted`` -------------------------------------- -*This option is commented out by default.* - -Flag indicating whether to allocate on or off heap when the sstable buffer -pool is exhausted, that is when it has exceeded the maximum memory -file_cache_size_in_mb, beyond which it will not cache buffers but allocate on request. - - -*Default Value:* true - -``disk_optimization_strategy`` ------------------------------- -*This option is commented out by default.* - -The strategy for optimizing disk read -Possible values are: -ssd (for solid state disks, the default) -spinning (for spinning disks) - -*Default Value:* ssd - -``memtable_heap_space_in_mb`` ------------------------------ -*This option is commented out by default.* - -Total permitted memory to use for memtables. Cassandra will stop -accepting writes when the limit is exceeded until a flush completes, -and will trigger a flush based on memtable_cleanup_threshold -If omitted, Cassandra will set both to 1/4 the size of the heap. - -*Default Value:* 2048 - -``memtable_offheap_space_in_mb`` --------------------------------- -*This option is commented out by default.* - -*Default Value:* 2048 - -``memtable_cleanup_threshold`` ------------------------------- -*This option is commented out by default.* - -Ratio of occupied non-flushing memtable size to total permitted size -that will trigger a flush of the largest memtable. Larger mct will -mean larger flushes and hence less compaction, but also less concurrent -flush activity which can make it difficult to keep your disks fed -under heavy write load. - -memtable_cleanup_threshold defaults to 1 / (memtable_flush_writers + 1) - -*Default Value:* 0.11 - -``memtable_allocation_type`` ----------------------------- - -Specify the way Cassandra allocates and manages memtable memory. -Options are: - -heap_buffers - on heap nio buffers - -offheap_buffers - off heap (direct) nio buffers - -offheap_objects - off heap objects - -*Default Value:* heap_buffers - -``commitlog_total_space_in_mb`` -------------------------------- -*This option is commented out by default.* - -Total space to use for commit logs on disk. - -If space gets above this value, Cassandra will flush every dirty CF -in the oldest segment and remove it. So a small total commitlog space -will tend to cause more flush activity on less-active columnfamilies. - -The default value is the smaller of 8192, and 1/4 of the total space -of the commitlog volume. - - -*Default Value:* 8192 - -``memtable_flush_writers`` --------------------------- -*This option is commented out by default.* - -This sets the amount of memtable flush writer threads. These will -be blocked by disk io, and each one will hold a memtable in memory -while blocked. - -memtable_flush_writers defaults to one per data_file_directory. - -If your data directories are backed by SSD, you can increase this, but -avoid having memtable_flush_writers * data_file_directories > number of cores - -*Default Value:* 1 - -``index_summary_capacity_in_mb`` --------------------------------- - -A fixed memory pool size in MB for for SSTable index summaries. If left -empty, this will default to 5% of the heap size. If the memory usage of -all index summaries exceeds this limit, SSTables with low read rates will -shrink their index summaries in order to meet this limit. However, this -is a best-effort process. In extreme conditions Cassandra may need to use -more than this amount of memory. - -``index_summary_resize_interval_in_minutes`` --------------------------------------------- - -How frequently index summaries should be resampled. This is done -periodically to redistribute memory from the fixed-size pool to sstables -proportional their recent read rates. Setting to -1 will disable this -process, leaving existing index summaries at their current sampling level. - -*Default Value:* 60 - -``trickle_fsync`` ------------------ - -Whether to, when doing sequential writing, fsync() at intervals in -order to force the operating system to flush the dirty -buffers. Enable this to avoid sudden dirty buffer flushing from -impacting read latencies. Almost always a good idea on SSDs; not -necessarily on platters. - -*Default Value:* false - -``trickle_fsync_interval_in_kb`` --------------------------------- - -*Default Value:* 10240 - -``storage_port`` ----------------- - -TCP port, for commands and data -For security reasons, you should not expose this port to the internet. Firewall it if needed. - -*Default Value:* 7000 - -``ssl_storage_port`` --------------------- - -SSL port, for encrypted communication. Unused unless enabled in -encryption_options -For security reasons, you should not expose this port to the internet. Firewall it if needed. - -*Default Value:* 7001 - -``listen_address`` ------------------- - -Address or interface to bind to and tell other Cassandra nodes to connect to. -You _must_ change this if you want multiple nodes to be able to communicate! - -Set listen_address OR listen_interface, not both. - -Leaving it blank leaves it up to InetAddress.getLocalHost(). This -will always do the Right Thing _if_ the node is properly configured -(hostname, name resolution, etc), and the Right Thing is to use the -address associated with the hostname (it might not be). - -Setting listen_address to 0.0.0.0 is always wrong. - - -*Default Value:* localhost - -``listen_interface`` --------------------- -*This option is commented out by default.* - -Set listen_address OR listen_interface, not both. Interfaces must correspond -to a single address, IP aliasing is not supported. - -*Default Value:* eth0 - -``listen_interface_prefer_ipv6`` --------------------------------- -*This option is commented out by default.* - -If you choose to specify the interface by name and the interface has an ipv4 and an ipv6 address -you can specify which should be chosen using listen_interface_prefer_ipv6. If false the first ipv4 -address will be used. If true the first ipv6 address will be used. Defaults to false preferring -ipv4. If there is only one address it will be selected regardless of ipv4/ipv6. - -*Default Value:* false - -``broadcast_address`` ---------------------- -*This option is commented out by default.* - -Address to broadcast to other Cassandra nodes -Leaving this blank will set it to the same value as listen_address - -*Default Value:* 1.2.3.4 - -``listen_on_broadcast_address`` -------------------------------- -*This option is commented out by default.* - -When using multiple physical network interfaces, set this -to true to listen on broadcast_address in addition to -the listen_address, allowing nodes to communicate in both -interfaces. -Ignore this property if the network configuration automatically -routes between the public and private networks such as EC2. - -*Default Value:* false - -``internode_authenticator`` ---------------------------- -*This option is commented out by default.* - -Internode authentication backend, implementing IInternodeAuthenticator; -used to allow/disallow connections from peer nodes. - -*Default Value:* org.apache.cassandra.auth.AllowAllInternodeAuthenticator - -``start_native_transport`` --------------------------- - -Whether to start the native transport server. -Please note that the address on which the native transport is bound is the -same as the rpc_address. The port however is different and specified below. - -*Default Value:* true - -``native_transport_port`` -------------------------- -port for the CQL native transport to listen for clients on -For security reasons, you should not expose this port to the internet. Firewall it if needed. - -*Default Value:* 9042 - -``native_transport_port_ssl`` ------------------------------ -*This option is commented out by default.* -Enabling native transport encryption in client_encryption_options allows you to either use -encryption for the standard port or to use a dedicated, additional port along with the unencrypted -standard native_transport_port. -Enabling client encryption and keeping native_transport_port_ssl disabled will use encryption -for native_transport_port. Setting native_transport_port_ssl to a different value -from native_transport_port will use encryption for native_transport_port_ssl while -keeping native_transport_port unencrypted. - -*Default Value:* 9142 - -``native_transport_max_threads`` --------------------------------- -*This option is commented out by default.* -The maximum threads for handling requests when the native transport is used. -This is similar to rpc_max_threads though the default differs slightly (and -there is no native_transport_min_threads, idle threads will always be stopped -after 30 seconds). - -*Default Value:* 128 - -``native_transport_max_frame_size_in_mb`` ------------------------------------------ -*This option is commented out by default.* - -The maximum size of allowed frame. Frame (requests) larger than this will -be rejected as invalid. The default is 256MB. If you're changing this parameter, -you may want to adjust max_value_size_in_mb accordingly. - -*Default Value:* 256 - -``native_transport_max_concurrent_connections`` ------------------------------------------------ -*This option is commented out by default.* - -The maximum number of concurrent client connections. -The default is -1, which means unlimited. - -*Default Value:* -1 - -``native_transport_max_concurrent_connections_per_ip`` ------------------------------------------------------- -*This option is commented out by default.* - -The maximum number of concurrent client connections per source ip. -The default is -1, which means unlimited. - -*Default Value:* -1 - -``start_rpc`` -------------- - -Whether to start the thrift rpc server. - -*Default Value:* false - -``rpc_address`` ---------------- - -The address or interface to bind the Thrift RPC service and native transport -server to. - -Set rpc_address OR rpc_interface, not both. - -Leaving rpc_address blank has the same effect as on listen_address -(i.e. it will be based on the configured hostname of the node). - -Note that unlike listen_address, you can specify 0.0.0.0, but you must also -set broadcast_rpc_address to a value other than 0.0.0.0. - -For security reasons, you should not expose this port to the internet. Firewall it if needed. - -*Default Value:* localhost - -``rpc_interface`` ------------------ -*This option is commented out by default.* - -Set rpc_address OR rpc_interface, not both. Interfaces must correspond -to a single address, IP aliasing is not supported. - -*Default Value:* eth1 - -``rpc_interface_prefer_ipv6`` ------------------------------ -*This option is commented out by default.* - -If you choose to specify the interface by name and the interface has an ipv4 and an ipv6 address -you can specify which should be chosen using rpc_interface_prefer_ipv6. If false the first ipv4 -address will be used. If true the first ipv6 address will be used. Defaults to false preferring -ipv4. If there is only one address it will be selected regardless of ipv4/ipv6. - -*Default Value:* false - -``rpc_port`` ------------- - -port for Thrift to listen for clients on - -*Default Value:* 9160 - -``broadcast_rpc_address`` -------------------------- -*This option is commented out by default.* - -RPC address to broadcast to drivers and other Cassandra nodes. This cannot -be set to 0.0.0.0. If left blank, this will be set to the value of -rpc_address. If rpc_address is set to 0.0.0.0, broadcast_rpc_address must -be set. - -*Default Value:* 1.2.3.4 - -``rpc_keepalive`` ------------------ - -enable or disable keepalive on rpc/native connections - -*Default Value:* true - -``rpc_server_type`` -------------------- - -Cassandra provides two out-of-the-box options for the RPC Server: - -sync - One thread per thrift connection. For a very large number of clients, memory - will be your limiting factor. On a 64 bit JVM, 180KB is the minimum stack size - per thread, and that will correspond to your use of virtual memory (but physical memory - may be limited depending on use of stack space). - -hsha - Stands for "half synchronous, half asynchronous." All thrift clients are handled - asynchronously using a small number of threads that does not vary with the amount - of thrift clients (and thus scales well to many clients). The rpc requests are still - synchronous (one thread per active request). If hsha is selected then it is essential - that rpc_max_threads is changed from the default value of unlimited. - -The default is sync because on Windows hsha is about 30% slower. On Linux, -sync/hsha performance is about the same, with hsha of course using less memory. - -Alternatively, can provide your own RPC server by providing the fully-qualified class name -of an o.a.c.t.TServerFactory that can create an instance of it. - -*Default Value:* sync - -``rpc_min_threads`` -------------------- -*This option is commented out by default.* - -Uncomment rpc_min|max_thread to set request pool size limits. - -Regardless of your choice of RPC server (see above), the number of maximum requests in the -RPC thread pool dictates how many concurrent requests are possible (but if you are using the sync -RPC server, it also dictates the number of clients that can be connected at all). - -The default is unlimited and thus provides no protection against clients overwhelming the server. You are -encouraged to set a maximum that makes sense for you in production, but do keep in mind that -rpc_max_threads represents the maximum number of client requests this server may execute concurrently. - - -*Default Value:* 16 - -``rpc_max_threads`` -------------------- -*This option is commented out by default.* - -*Default Value:* 2048 - -``rpc_send_buff_size_in_bytes`` -------------------------------- -*This option is commented out by default.* - -uncomment to set socket buffer sizes on rpc connections - -``rpc_recv_buff_size_in_bytes`` -------------------------------- -*This option is commented out by default.* - -``internode_send_buff_size_in_bytes`` -------------------------------------- -*This option is commented out by default.* - -Uncomment to set socket buffer size for internode communication -Note that when setting this, the buffer size is limited by net.core.wmem_max -and when not setting it it is defined by net.ipv4.tcp_wmem -See also: -/proc/sys/net/core/wmem_max -/proc/sys/net/core/rmem_max -/proc/sys/net/ipv4/tcp_wmem -/proc/sys/net/ipv4/tcp_wmem -and 'man tcp' - -``internode_recv_buff_size_in_bytes`` -------------------------------------- -*This option is commented out by default.* - -Uncomment to set socket buffer size for internode communication -Note that when setting this, the buffer size is limited by net.core.wmem_max -and when not setting it it is defined by net.ipv4.tcp_wmem - -``thrift_framed_transport_size_in_mb`` --------------------------------------- - -Frame size for thrift (maximum message length). - -*Default Value:* 15 - -``incremental_backups`` ------------------------ - -Set to true to have Cassandra create a hard link to each sstable -flushed or streamed locally in a backups/ subdirectory of the -keyspace data. Removing these links is the operator's -responsibility. - -*Default Value:* false - -``snapshot_before_compaction`` ------------------------------- - -Whether or not to take a snapshot before each compaction. Be -careful using this option, since Cassandra won't clean up the -snapshots for you. Mostly useful if you're paranoid when there -is a data format change. - -*Default Value:* false - -``auto_snapshot`` ------------------ - -Whether or not a snapshot is taken of the data before keyspace truncation -or dropping of column families. The STRONGLY advised default of true -should be used to provide data safety. If you set this flag to false, you will -lose data on truncation or drop. - -*Default Value:* true - -``column_index_size_in_kb`` ---------------------------- - -Granularity of the collation index of rows within a partition. -Increase if your rows are large, or if you have a very large -number of rows per partition. The competing goals are these: - -- a smaller granularity means more index entries are generated - and looking up rows withing the partition by collation column - is faster -- but, Cassandra will keep the collation index in memory for hot - rows (as part of the key cache), so a larger granularity means - you can cache more hot rows - -*Default Value:* 64 - -``column_index_cache_size_in_kb`` ---------------------------------- - -Per sstable indexed key cache entries (the collation index in memory -mentioned above) exceeding this size will not be held on heap. -This means that only partition information is held on heap and the -index entries are read from disk. - -Note that this size refers to the size of the -serialized index information and not the size of the partition. - -*Default Value:* 2 - -``concurrent_compactors`` -------------------------- -*This option is commented out by default.* - -Number of simultaneous compactions to allow, NOT including -validation "compactions" for anti-entropy repair. Simultaneous -compactions can help preserve read performance in a mixed read/write -workload, by mitigating the tendency of small sstables to accumulate -during a single long running compactions. The default is usually -fine and if you experience problems with compaction running too -slowly or too fast, you should look at -compaction_throughput_mb_per_sec first. - -concurrent_compactors defaults to the smaller of (number of disks, -number of cores), with a minimum of 2 and a maximum of 8. - -If your data directories are backed by SSD, you should increase this -to the number of cores. - -*Default Value:* 1 - -``compaction_throughput_mb_per_sec`` ------------------------------------- - -Throttles compaction to the given total throughput across the entire -system. The faster you insert data, the faster you need to compact in -order to keep the sstable count down, but in general, setting this to -16 to 32 times the rate you are inserting data is more than sufficient. -Setting this to 0 disables throttling. Note that this account for all types -of compaction, including validation compaction. - -*Default Value:* 16 - -``sstable_preemptive_open_interval_in_mb`` ------------------------------------------- - -When compacting, the replacement sstable(s) can be opened before they -are completely written, and used in place of the prior sstables for -any range that has been written. This helps to smoothly transfer reads -between the sstables, reducing page cache churn and keeping hot rows hot - -*Default Value:* 50 - -``stream_throughput_outbound_megabits_per_sec`` ------------------------------------------------ -*This option is commented out by default.* - -Throttles all outbound streaming file transfers on this node to the -given total throughput in Mbps. This is necessary because Cassandra does -mostly sequential IO when streaming data during bootstrap or repair, which -can lead to saturating the network connection and degrading rpc performance. -When unset, the default is 200 Mbps or 25 MB/s. - -*Default Value:* 200 - -``inter_dc_stream_throughput_outbound_megabits_per_sec`` --------------------------------------------------------- -*This option is commented out by default.* - -Throttles all streaming file transfer between the datacenters, -this setting allows users to throttle inter dc stream throughput in addition -to throttling all network stream traffic as configured with -stream_throughput_outbound_megabits_per_sec -When unset, the default is 200 Mbps or 25 MB/s - -*Default Value:* 200 - -``read_request_timeout_in_ms`` ------------------------------- - -How long the coordinator should wait for read operations to complete - -*Default Value:* 5000 - -``range_request_timeout_in_ms`` -------------------------------- -How long the coordinator should wait for seq or index scans to complete - -*Default Value:* 10000 - -``write_request_timeout_in_ms`` -------------------------------- -How long the coordinator should wait for writes to complete - -*Default Value:* 2000 - -``counter_write_request_timeout_in_ms`` ---------------------------------------- -How long the coordinator should wait for counter writes to complete - -*Default Value:* 5000 - -``cas_contention_timeout_in_ms`` --------------------------------- -How long a coordinator should continue to retry a CAS operation -that contends with other proposals for the same row - -*Default Value:* 1000 - -``truncate_request_timeout_in_ms`` ----------------------------------- -How long the coordinator should wait for truncates to complete -(This can be much longer, because unless auto_snapshot is disabled -we need to flush first so we can snapshot before removing the data.) - -*Default Value:* 60000 - -``request_timeout_in_ms`` -------------------------- -The default timeout for other, miscellaneous operations - -*Default Value:* 10000 - -``cross_node_timeout`` ----------------------- - -Enable operation timeout information exchange between nodes to accurately -measure request timeouts. If disabled, replicas will assume that requests -were forwarded to them instantly by the coordinator, which means that -under overload conditions we will waste that much extra time processing -already-timed-out requests. - -Warning: before enabling this property make sure to ntp is installed -and the times are synchronized between the nodes. - -*Default Value:* false - -``streaming_socket_timeout_in_ms`` ----------------------------------- -*This option is commented out by default.* - -Set socket timeout for streaming operation. -The stream session is failed if no data/ack is received by any of the participants -within that period, which means this should also be sufficient to stream a large -sstable or rebuild table indexes. -Default value is 86400000ms, which means stale streams timeout after 24 hours. -A value of zero means stream sockets should never time out. - -*Default Value:* 86400000 - -``phi_convict_threshold`` -------------------------- -*This option is commented out by default.* - -phi value that must be reached for a host to be marked down. -most users should never need to adjust this. - -*Default Value:* 8 - -``endpoint_snitch`` -------------------- - -endpoint_snitch -- Set this to a class that implements -IEndpointSnitch. The snitch has two functions: - -- it teaches Cassandra enough about your network topology to route - requests efficiently -- it allows Cassandra to spread replicas around your cluster to avoid - correlated failures. It does this by grouping machines into - "datacenters" and "racks." Cassandra will do its best not to have - more than one replica on the same "rack" (which may not actually - be a physical location) - -IF YOU CHANGE THE SNITCH AFTER DATA IS INSERTED INTO THE CLUSTER, -YOU MUST RUN A FULL REPAIR, SINCE THE SNITCH AFFECTS WHERE REPLICAS -ARE PLACED. - -IF THE RACK A REPLICA IS PLACED IN CHANGES AFTER THE REPLICA HAS BEEN -ADDED TO A RING, THE NODE MUST BE DECOMMISSIONED AND REBOOTSTRAPPED. - -Out of the box, Cassandra provides: - -SimpleSnitch: - Treats Strategy order as proximity. This can improve cache - locality when disabling read repair. Only appropriate for - single-datacenter deployments. - -GossipingPropertyFileSnitch - This should be your go-to snitch for production use. The rack - and datacenter for the local node are defined in - cassandra-rackdc.properties and propagated to other nodes via - gossip. If cassandra-topology.properties exists, it is used as a - fallback, allowing migration from the PropertyFileSnitch. - -PropertyFileSnitch: - Proximity is determined by rack and data center, which are - explicitly configured in cassandra-topology.properties. - -Ec2Snitch: - Appropriate for EC2 deployments in a single Region. Loads Region - and Availability Zone information from the EC2 API. The Region is - treated as the datacenter, and the Availability Zone as the rack. - Only private IPs are used, so this will not work across multiple - Regions. - -Ec2MultiRegionSnitch: - Uses public IPs as broadcast_address to allow cross-region - connectivity. (Thus, you should set seed addresses to the public - IP as well.) You will need to open the storage_port or - ssl_storage_port on the public IP firewall. (For intra-Region - traffic, Cassandra will switch to the private IP after - establishing a connection.) - -RackInferringSnitch: - Proximity is determined by rack and data center, which are - assumed to correspond to the 3rd and 2nd octet of each node's IP - address, respectively. Unless this happens to match your - deployment conventions, this is best used as an example of - writing a custom Snitch class and is provided in that spirit. - -You can use a custom Snitch by setting this to the full class name -of the snitch, which will be assumed to be on your classpath. - -*Default Value:* SimpleSnitch - -``dynamic_snitch_update_interval_in_ms`` ----------------------------------------- - -controls how often to perform the more expensive part of host score -calculation - -*Default Value:* 100 - -``dynamic_snitch_reset_interval_in_ms`` ---------------------------------------- -controls how often to reset all host scores, allowing a bad host to -possibly recover - -*Default Value:* 600000 - -``dynamic_snitch_badness_threshold`` ------------------------------------- -if set greater than zero and read_repair_chance is < 1.0, this will allow -'pinning' of replicas to hosts in order to increase cache capacity. -The badness threshold will control how much worse the pinned host has to be -before the dynamic snitch will prefer other replicas over it. This is -expressed as a double which represents a percentage. Thus, a value of -0.2 means Cassandra would continue to prefer the static snitch values -until the pinned host was 20% worse than the fastest. - -*Default Value:* 0.1 - -``request_scheduler`` ---------------------- - -request_scheduler -- Set this to a class that implements -RequestScheduler, which will schedule incoming client requests -according to the specific policy. This is useful for multi-tenancy -with a single Cassandra cluster. -NOTE: This is specifically for requests from the client and does -not affect inter node communication. -org.apache.cassandra.scheduler.NoScheduler - No scheduling takes place -org.apache.cassandra.scheduler.RoundRobinScheduler - Round robin of -client requests to a node with a separate queue for each -request_scheduler_id. The scheduler is further customized by -request_scheduler_options as described below. - -*Default Value:* org.apache.cassandra.scheduler.NoScheduler - -``request_scheduler_options`` ------------------------------ -*This option is commented out by default.* - -Scheduler Options vary based on the type of scheduler - -NoScheduler - Has no options - -RoundRobin - throttle_limit - The throttle_limit is the number of in-flight - requests per client. Requests beyond - that limit are queued up until - running requests can complete. - The value of 80 here is twice the number of - concurrent_reads + concurrent_writes. - default_weight - default_weight is optional and allows for - overriding the default which is 1. - weights - Weights are optional and will default to 1 or the - overridden default_weight. The weight translates into how - many requests are handled during each turn of the - RoundRobin, based on the scheduler id. - - -*Default Value (complex option)*:: - - # throttle_limit: 80 - # default_weight: 5 - # weights: - # Keyspace1: 1 - # Keyspace2: 5 - -``request_scheduler_id`` ------------------------- -*This option is commented out by default.* -request_scheduler_id -- An identifier based on which to perform -the request scheduling. Currently the only valid option is keyspace. - -*Default Value:* keyspace - -``server_encryption_options`` ------------------------------ - -Enable or disable inter-node encryption -JVM defaults for supported SSL socket protocols and cipher suites can -be replaced using custom encryption options. This is not recommended -unless you have policies in place that dictate certain settings, or -need to disable vulnerable ciphers or protocols in case the JVM cannot -be updated. -FIPS compliant settings can be configured at JVM level and should not -involve changing encryption settings here: -https://docs.oracle.com/javase/8/docs/technotes/guides/security/jsse/FIPS.html -*NOTE* No custom encryption options are enabled at the moment -The available internode options are : all, none, dc, rack - -If set to dc cassandra will encrypt the traffic between the DCs -If set to rack cassandra will encrypt the traffic between the racks - -The passwords used in these options must match the passwords used when generating -the keystore and truststore. For instructions on generating these files, see: -http://download.oracle.com/javase/6/docs/technotes/guides/security/jsse/JSSERefGuide.html#CreateKeystore - - -*Default Value (complex option)*:: - - internode_encryption: none - keystore: conf/.keystore - keystore_password: cassandra - truststore: conf/.truststore - truststore_password: cassandra - # More advanced defaults below: - # protocol: TLS - # algorithm: SunX509 - # store_type: JKS - # cipher_suites: [TLS_RSA_WITH_AES_128_CBC_SHA,TLS_RSA_WITH_AES_256_CBC_SHA,TLS_DHE_RSA_WITH_AES_128_CBC_SHA,TLS_DHE_RSA_WITH_AES_256_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA] - # require_client_auth: false - # require_endpoint_verification: false - -``client_encryption_options`` ------------------------------ -enable or disable client/server encryption. - -*Default Value (complex option)*:: - - enabled: false - # If enabled and optional is set to true encrypted and unencrypted connections are handled. - optional: false - keystore: conf/.keystore - keystore_password: cassandra - # require_client_auth: false - # Set trustore and truststore_password if require_client_auth is true - # truststore: conf/.truststore - # truststore_password: cassandra - # More advanced defaults below: - # protocol: TLS - # algorithm: SunX509 - # store_type: JKS - # cipher_suites: [TLS_RSA_WITH_AES_128_CBC_SHA,TLS_RSA_WITH_AES_256_CBC_SHA,TLS_DHE_RSA_WITH_AES_128_CBC_SHA,TLS_DHE_RSA_WITH_AES_256_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA] - -``internode_compression`` -------------------------- -internode_compression controls whether traffic between nodes is -compressed. -Can be: - -all - all traffic is compressed - -dc - traffic between different datacenters is compressed - -none - nothing is compressed. - -*Default Value:* dc - -``inter_dc_tcp_nodelay`` ------------------------- - -Enable or disable tcp_nodelay for inter-dc communication. -Disabling it will result in larger (but fewer) network packets being sent, -reducing overhead from the TCP protocol itself, at the cost of increasing -latency if you block for cross-datacenter responses. - -*Default Value:* false - -``tracetype_query_ttl`` ------------------------ - -TTL for different trace types used during logging of the repair process. - -*Default Value:* 86400 - -``tracetype_repair_ttl`` ------------------------- - -*Default Value:* 604800 - -``enable_user_defined_functions`` ---------------------------------- - -UDFs (user defined functions) are disabled by default. -As of Cassandra 3.0 there is a sandbox in place that should prevent execution of evil code. - -*Default Value:* false - -``enable_scripted_user_defined_functions`` ------------------------------------------- - -Enables scripted UDFs (JavaScript UDFs). -Java UDFs are always enabled, if enable_user_defined_functions is true. -Enable this option to be able to use UDFs with "language javascript" or any custom JSR-223 provider. -This option has no effect, if enable_user_defined_functions is false. - -*Default Value:* false - -``windows_timer_interval`` --------------------------- - -The default Windows kernel timer and scheduling resolution is 15.6ms for power conservation. -Lowering this value on Windows can provide much tighter latency and better throughput, however -some virtualized environments may see a negative performance impact from changing this setting -below their system default. The sysinternals 'clockres' tool can confirm your system's default -setting. - -*Default Value:* 1 - -``transparent_data_encryption_options`` ---------------------------------------- - - -Enables encrypting data at-rest (on disk). Different key providers can be plugged in, but the default reads from -a JCE-style keystore. A single keystore can hold multiple keys, but the one referenced by -the "key_alias" is the only key that will be used for encrypt opertaions; previously used keys -can still (and should!) be in the keystore and will be used on decrypt operations -(to handle the case of key rotation). - -It is strongly recommended to download and install Java Cryptography Extension (JCE) -Unlimited Strength Jurisdiction Policy Files for your version of the JDK. -(current link: http://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html) - -Currently, only the following file types are supported for transparent data encryption, although -more are coming in future cassandra releases: commitlog, hints - -*Default Value (complex option)*:: - - enabled: false - chunk_length_kb: 64 - cipher: AES/CBC/PKCS5Padding - key_alias: testing:1 - # CBC IV length for AES needs to be 16 bytes (which is also the default size) - # iv_length: 16 - key_provider: - - class_name: org.apache.cassandra.security.JKSKeyProvider - parameters: - - keystore: conf/.keystore - keystore_password: cassandra - store_type: JCEKS - key_password: cassandra - -``tombstone_warn_threshold`` ----------------------------- - -#################### -SAFETY THRESHOLDS # -#################### - -When executing a scan, within or across a partition, we need to keep the -tombstones seen in memory so we can return them to the coordinator, which -will use them to make sure other replicas also know about the deleted rows. -With workloads that generate a lot of tombstones, this can cause performance -problems and even exaust the server heap. -(http://www.datastax.com/dev/blog/cassandra-anti-patterns-queues-and-queue-like-datasets) -Adjust the thresholds here if you understand the dangers and want to -scan more tombstones anyway. These thresholds may also be adjusted at runtime -using the StorageService mbean. - -*Default Value:* 1000 - -``tombstone_failure_threshold`` -------------------------------- - -*Default Value:* 100000 - -``batch_size_warn_threshold_in_kb`` ------------------------------------ - -Log WARN on any batch size exceeding this value. 5kb per batch by default. -Caution should be taken on increasing the size of this threshold as it can lead to node instability. - -*Default Value:* 5 - -``batch_size_fail_threshold_in_kb`` ------------------------------------ - -Fail any batch exceeding this value. 50kb (10x warn threshold) by default. - -*Default Value:* 50 - -``unlogged_batch_across_partitions_warn_threshold`` ---------------------------------------------------- - -Log WARN on any batches not of type LOGGED than span across more partitions than this limit - -*Default Value:* 10 - -``compaction_large_partition_warning_threshold_mb`` ---------------------------------------------------- - -Log a warning when compacting partitions larger than this value - -*Default Value:* 100 - -``gc_warn_threshold_in_ms`` ---------------------------- - -GC Pauses greater than gc_warn_threshold_in_ms will be logged at WARN level -Adjust the threshold based on your application throughput requirement -By default, Cassandra logs GC Pauses greater than 200 ms at INFO level - -*Default Value:* 1000 - -``max_value_size_in_mb`` ------------------------- -*This option is commented out by default.* - -Maximum size of any value in SSTables. Safety measure to detect SSTable corruption -early. Any value size larger than this threshold will result into marking an SSTable -as corrupted. - -*Default Value:* 256
