Thank you so much Jeff! I will bump to Cassandra 2.1.9 and update this thread with the results!
Thanks, Venkatesh On Mon, Sep 21, 2015 at 2:19 PM, Jeff Jirsa <jeff.ji...@crowdstrike.com> wrote: > The timestamp involed here isn’t the one defined in the schema, it’s the > timestamp written on each cell when you apply a mutation (write). > > That timestamp is the one returned by WRITETIME(), and visible in > sstablemetadata – it’s not visible in the schema directly. > > Failing to have the proper unit (milliseconds vs microseconds) could > certainly cause confusion. > > > > From: Venkatesh Arivazhagan > Reply-To: "user@cassandra.apache.org" > Date: Monday, September 21, 2015 at 1:41 PM > To: "user@cassandra.apache.org" > Subject: Re: Help with tombstones and compaction > > Thank you for your reply Jeff! > > I will switch to Cassandra 2.1.9. > > Quick follow up question: Does the schema, settings I have setup look > alright? My timestamp column's type is blob - I was wondering if this could > confuse DTCS? > > On Sun, Sep 20, 2015 at 3:37 PM, Jeff Jirsa <jeff.ji...@crowdstrike.com> > wrote: > >> 2.1.4 is getting pretty old. There’s a DTCS deletion tweak in 2.1.5 ( >> https://issues.apache.org/jira/browse/CASSANDRA-8359 ) that may help you. >> >> 2.1.5 and 2.1.6 have some memory leak issues in DTCS, so go to 2.1.7 or >> newer (probably 2.1.9 unless you have a compelling reason not to go to >> 2.1.9) >> >> >> From: Venkatesh Arivazhagan >> Reply-To: "user@cassandra.apache.org" >> Date: Sunday, September 20, 2015 at 2:48 PM >> To: "user@cassandra.apache.org" >> Subject: Help with tombstones and compaction >> >> Hi Guys, >> >> I have a Cassandra 2.1.4 cluster with 14 nodes. I am using it primarily >> for storing time series data collected via KairosDB. >> The default TTL for data inserted into the column family named >> data_points is 12hrs. I have also set the gc_grace_seconds to 12 hrs. >> In-spite of this my disk space keeps on increasing and it looks like >> tombstones are never dropped. >> >> It looks like compactions are happening on a regular basis. The SSTable >> count does not seem outrageous either. It is constantly between ~10 to ~22. >> >> Am I doing anything wrong? Is there a way to mitigate this? >> >> Attached: >> * DESC output for my keyspace >> * Disk usage graph >> * LiveSSTable Count graph >> >> >> -------------------------------------------------------------------------------------------------------------------------- >> >> CREATE KEYSPACE kairosdb WITH replication = {'class': 'SimpleStrategy', >> 'replication_factor': '3'} AND durable_writes = true; >> >> CREATE TABLE kairosdb.data_points ( >> key blob, >> column1 blob, >> value blob, >> PRIMARY KEY (key, column1) >> ) WITH COMPACT STORAGE >> AND CLUSTERING ORDER BY (column1 ASC) >> AND bloom_filter_fp_chance = 0.01 >> AND caching = '{"keys":"ALL", "rows_per_partition":"NONE"}' >> AND comment = '' >> AND compaction = {'max_sstable_age_days': '365', 'base_time_seconds': >> '3600', 'max_threshold': '32', 'timestamp_resolution': 'MILLISECONDS', >> 'enabled': 'true', 'tombstone_compaction_interval': '1', 'min_threshold': >> '4', 'tombstone_threshold': '.1', 'class': >> 'org.apache.cassandra.db.compaction.DateTieredCompactionStrategy'} >> AND compression = {'sstable_compression': >> 'org.apache.cassandra.io.compress.LZ4Compressor'} >> AND dclocal_read_repair_chance = 0.1 >> AND default_time_to_live = 43200 >> AND gc_grace_seconds = 43200 >> AND max_index_interval = 2048 >> AND memtable_flush_period_in_ms = 0 >> AND min_index_interval = 128 >> AND read_repair_chance = 0.1 >> AND speculative_retry = 'NONE'; >> >> CREATE TABLE kairosdb.row_key_index ( >> key blob, >> column1 blob, >> value blob, >> PRIMARY KEY (key, column1) >> ) WITH COMPACT STORAGE >> AND CLUSTERING ORDER BY (column1 ASC) >> AND bloom_filter_fp_chance = 0.01 >> AND caching = '{"keys":"ALL", "rows_per_partition":"NONE"}' >> AND comment = '' >> AND compaction = {'min_threshold': '4', 'class': >> 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', >> 'max_threshold': '32'} >> AND compression = {'sstable_compression': >> 'org.apache.cassandra.io.compress.LZ4Compressor'} >> AND dclocal_read_repair_chance = 0.1 >> AND default_time_to_live = 0 >> AND gc_grace_seconds = 43200 >> AND max_index_interval = 2048 >> AND memtable_flush_period_in_ms = 0 >> AND min_index_interval = 128 >> AND read_repair_chance = 0.1 >> AND speculative_retry = 'NONE'; >> >> CREATE TABLE kairosdb.string_index ( >> key blob, >> column1 text, >> value blob, >> PRIMARY KEY (key, column1) >> ) WITH COMPACT STORAGE >> AND CLUSTERING ORDER BY (column1 ASC) >> AND bloom_filter_fp_chance = 0.01 >> AND caching = '{"keys":"ALL", "rows_per_partition":"NONE"}' >> AND comment = '' >> AND compaction = {'min_threshold': '4', 'class': >> 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', >> 'max_threshold': '32'} >> AND compression = {'sstable_compression': >> 'org.apache.cassandra.io.compress.LZ4Compressor'} >> AND dclocal_read_repair_chance = 0.1 >> AND default_time_to_live = 0 >> AND gc_grace_seconds = 43200 >> AND max_index_interval = 2048 >> AND memtable_flush_period_in_ms = 0 >> AND min_index_interval = 128 >> AND read_repair_chance = 0.1 >> AND speculative_retry = 'NONE'; >> >> -------------------------------------------------------------------------------------------------------------------------- >> > >
