RE: shutdown by drain
More of it, Cassandra 0.8.6 still leaves all commit logs under Windows. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 J. Jasinskio 16C, LT-01112 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.-Original Message- From: Radim Kolar [mailto:h...@sendmail.cz] Sent: Friday, September 23, 2011 12:04 To: user@cassandra.apache.org Subject: Re: shutdown by drain Dne 10.9.2011 21:48, Chris Goffinet napsal(a): For things like rolling restarts, we do: disablethrift disablegossip (...wait for all nodes to see this node go down..) drain I discovered problem with this advice. If i do nodetool drain before killing node nodetool returns just after flush and stuff disabling is finished on cassandra node. But flush can trigger possible compaction and if you kill node after drain it will interrupt compaction in progress resulting in wasted disk space. I am not sure if tmp files are cleaned on cassandra start.
How to enable JNA for Cassandra on Windows?
Hi,
I'm trying without success to enable JNA for Cassandra on Windows.
Tried to place JNA 3.3.0 libs jna.jar and platform.jar into Cassandra 0.8.6
lib dir, but getting in log:
Unable to link C library. Native methods will be disabled.
What is missed or what is wrong?
One thing I've found on inet about JNA and Windows is this sample:
// Library is c for unix and msvcrt for windows
String libName = c;
if (System.getProperty(os.name).contains(Windows))
{
libName = msvcrt;
}
// Loading dynamically the library
CInterface demo = (CInterface) Native.loadLibrary(libName, CInterface.class);
from http://www.scriptol.com/programming/jna.php
while in Cassandra:
try
{
Native.register(c);
}
catch (NoClassDefFoundError e)
{
logger.info(JNA not found. Native methods will be disabled.);
}
catch (UnsatisfiedLinkError e)
{
logger.info(Unable to link C library. Native methods will be
disabled.);
}
catch (NoSuchMethodError e)
{
logger.warn(Obsolete version of JNA present; unable to
register C library. Upgrade to JNA 3.2.7 or later);
}
Is it true that for Windows Cassandra should do something like:
if (System.getProperty(os.name).contains(Windows))
{
Native.register(msvcrt);
}
else
{
Native.register(c);
}
Thanks
Viktor
Re: Cassandra Statistics and Metrics
There's possibility to use command line JMX client with standard Zabbix agent to request JMX counters without incorporating zapcat into Cassandra or another Java app. I'm investigating this feature right now, will post results when finish. 2011/6/15 Viktor Jevdokimov vjevdoki...@gmail.com http://www.kjkoster.org/zapcat/Zapcat_JMX_Zabbix_Bridge.html 2011/6/14 Marcos Ortiz mlor...@uci.cu Where I can find the source code? El 6/14/2011 10:13 AM, Viktor Jevdokimov escribió: We're using open source monitoring solution Zabbix from http://www.zabbix.com/ using zapcat - not only for Cassandra but for the whole system. As MX4J tools plugin is supported by Cassandra, support of zapcat in Cassandra by default is welcome - we have to use a wrapper to start zapcat agent. 2011/6/14 Marcos Ortiz mlor...@uci.cu Regards to all. My team and me here on the University are working on a generic solution for Monitoring and Capacity Planning for Open Sources Databases, and one of the NoSQL db that we choosed to give it support is Cassandra. Where I can find all the metrics and statistics of Cassandra? I'm thinking for example: - Available space - Number of CF and all kind of metrics We are using for this development: Python + Django + Twisted + Orbited + jQuery. The idea behind is to build a Comet-based web application on top of these technologies. Any advice is welcome -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186 -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186
Re: Cassandra Statistics and Metrics
http://www.kjkoster.org/zapcat/Zapcat_JMX_Zabbix_Bridge.html 2011/6/14 Marcos Ortiz mlor...@uci.cu Where I can find the source code? El 6/14/2011 10:13 AM, Viktor Jevdokimov escribió: We're using open source monitoring solution Zabbix from http://www.zabbix.com/ using zapcat - not only for Cassandra but for the whole system. As MX4J tools plugin is supported by Cassandra, support of zapcat in Cassandra by default is welcome - we have to use a wrapper to start zapcat agent. 2011/6/14 Marcos Ortiz mlor...@uci.cu Regards to all. My team and me here on the University are working on a generic solution for Monitoring and Capacity Planning for Open Sources Databases, and one of the NoSQL db that we choosed to give it support is Cassandra. Where I can find all the metrics and statistics of Cassandra? I'm thinking for example: - Available space - Number of CF and all kind of metrics We are using for this development: Python + Django + Twisted + Orbited + jQuery. The idea behind is to build a Comet-based web application on top of these technologies. Any advice is welcome -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186 -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186
Re: possible 'coming back to life' bug with counters
What if it is OK for our case and we need counters with TTL? For us Counters and TTL both are important. After column is expired it is not important what value counter will have. Scanning millions rows just to delete expired ones is not a solution. 2011/6/14 Sylvain Lebresne sylv...@datastax.com As listed here: http://wiki.apache.org/cassandra/Counters, counter deletion is provided as a convenience for permanent deletion of counters but, because of the design of counters, it is never safe to issue an increment on a counter that has been deleted (that is, you will experience back to life behavior sometimes in that case). More precisely, you'd have to wait long enough after a deletion to start incrementing the counter again. But in the worst cases, long enough is something like gc_grace_seconds + major compaction. This is *not* something that is likely to change anytime soon (I don't think this is fixable with the current design for counters). -- Sylvain On Sat, Jun 11, 2011 at 3:54 AM, David Hawthorne dha...@3crowd.com wrote: Please take a look at this thread over in the hector-users mailing list: http://groups.google.com/group/hector-users/browse_thread/thread/99835159b9ea1766 It looks as if the deleted columns are coming back to life when they shouldn't be. I don't want to open a bug on something if it's already got one that I just couldn't find when I scanned the list of open bugs. I'm using hector 0.8 against cassandra 0.8 release. I can give you whatever logs or files you'd like.
Re: Cassandra Statistics and Metrics
We're using open source monitoring solution Zabbix from http://www.zabbix.com/ using zapcat - not only for Cassandra but for the whole system. As MX4J tools plugin is supported by Cassandra, support of zapcat in Cassandra by default is welcome - we have to use a wrapper to start zapcat agent. 2011/6/14 Marcos Ortiz mlor...@uci.cu Regards to all. My team and me here on the University are working on a generic solution for Monitoring and Capacity Planning for Open Sources Databases, and one of the NoSQL db that we choosed to give it support is Cassandra. Where I can find all the metrics and statistics of Cassandra? I'm thinking for example: - Available space - Number of CF and all kind of metrics We are using for this development: Python + Django + Twisted + Orbited + jQuery. The idea behind is to build a Comet-based web application on top of these technologies. Any advice is welcome -- Marcos Luís Ortíz Valmaseda Software Engineer (UCI) http://marcosluis2186.posterous.com http://twitter.com/marcosluis2186
Re: Reads and memory usage clarification
Everything as I thought, thank you! 2011/2/23 Matthew Dennis mden...@datastax.com Data is in Memtables from writes before they get flushed (based on first threshold of ops/size/time exceeded; all are configurable) to SSTables on disk. There is a keycache and a rowcache. The keycache caches offsets into SSTables for the rows. the rowcache caches the entire row. There is also the OS page cache which is heavily used. When a read happens, the keycache is updated with the information for the SSTables the row was eventually found in. If there are too many entries now in the keycache, some are ejected. Overall the keycache uses very little memory per entry and can cut your disk IO in half so it's a pretty big win. If you read an entire row it goes in the row cache. Like the keycache, this may result in older entries being ejected from the cache. If you insert lots of really large rows in the rowcache you can OOM your JVM. The rowcache is kept up to date with the memtables as writes come in. When a read comes in, C* will collect the data from the SSTables and Memtables and merge them together but data only goes into Memtables from writes. On Tue, Feb 22, 2011 at 3:32 AM, Viktor Jevdokimov vjevdoki...@gmail.comwrote: Hello, Write path is perfectly documented in architecture overview. I need Reads to be clarified: How memory is used 1. When data is in the Memtable 2. When data is in the SSTable How cache is used alongside with Memtable? Are records created in the Memtable from writes only or from reads also? What I need to know is, how Cassandra uses memory and Memtables for reads? Thenk you, Viktor
Reads and memory usage clarification
Hello, Write path is perfectly documented in architecture overview. I need Reads to be clarified: How memory is used 1. When data is in the Memtable 2. When data is in the SSTable How cache is used alongside with Memtable? Are records created in the Memtable from writes only or from reads also? What I need to know is, how Cassandra uses memory and Memtables for reads? Thenk you, Viktor
RE: Do supercolumns have a purpose?
SCFs are very useful and I hope lives forever. We need them! Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies.-Original Message- From: norman.mau...@googlemail.com [mailto:norman.mau...@googlemail.com] On Behalf Of Norman Maurer Sent: Wednesday, February 09, 2011 20:59 To: user@cassandra.apache.org Subject: Re: Do supercolumns have a purpose? I still think super-columns are useful you just need to be aware of the limitations... Bye, Norman 2011/2/9 Mike Malone m...@simplegeo.com: On Tue, Feb 8, 2011 at 2:03 AM, David Boxenhorn da...@lookin2.com wrote: Shaun, I agree with you, but marking them as deprecated is not good enough for me. I can't easily stop using supercolumns. I need an upgrade path. David, Cassandra is open source and community developed. The right thing to do is what's best for the community, which sometimes conflicts with what's best for individual users. Such strife should be minimized, it will never be eliminated. Luckily, because this is an open source, liberal licensed project, if you feel strongly about something you should feel free to add whatever features you want yourself. I'm sure other people in your situation will thank you for it. At a minimum I think it would behoove you to re-read some of the comments here re: why super columns aren't really needed and take another look at your data model and code. I would actually be quite surprised to find a use of super columns that could not be trivially converted to normal columns. In fact, it should be possible to do at the framework/client library layer - you probably wouldn't even need to change any application code. Mike On Tue, Feb 8, 2011 at 3:53 AM, Shaun Cutts sh...@cuttshome.net wrote: I'm a newbie here, but, with apologies for my presumptuousness, I think you should deprecate SuperColumns. They are already distracting you, and as the years go by the cost of supporting them as you add more and more functionality is only likely to get worse. It would be better to concentrate on making the core column families better (and I'm sure we can all think of lots of things we'd like). Just dropping SuperColumns would be bad for your reputation -- and for users like David who are currently using them. But if you mark them clearly as deprecated and explain why and what to do instead (perhaps putting a bit of effort into migration tools... or even a virtual layer supporting arbitrary hierarchical data), then you can drop them in a few years (when you get to 1.0, say), without people feeling betrayed. -- Shaun On Feb 6, 2011, at 3:48 AM, David Boxenhorn wrote: My main point was to say that it's think it is better to create tickets for what you want, rather than for something else completely different that would, as a by-product, give you what you want. Then let me say what I want: I want supercolumn families to have any feature that regular column families have. My data model is full of supercolumns. I used them, even though I knew it didn't *have to*, because they were there, which implied to me that I was supposed to use them for some good reason. Now I suspect that they will gradually become less and less functional, as features are added to regular column families and not supported for supercolumn families. On Fri, Feb 4, 2011 at 10:58 AM, Sylvain Lebresne sylv...@datastax.com wrote: On Fri, Feb 4, 2011 at 12:35 AM, Mike Malone m...@simplegeo.com wrote: On Thu, Feb 3, 2011 at 6:44 AM, Sylvain Lebresne sylv...@datastax.com wrote: On Thu, Feb 3, 2011 at 3:00 PM, David Boxenhorn da...@lookin2.com wrote: The advantage would be to enable secondary indexes on supercolumn families. Then I suggest opening a ticket for adding secondary indexes to supercolumn families and voting on it. This will be 1 or 2 order of magnitude less work than getting rid of super column internally, and probably a much better solution anyway. I realize that this is largely subjective, and on such matters code speaks louder than words, but I don't think I agree with you on the issue of which alternative is less work, or even which is a better solution. You are right, I put probably too much emphase in that sentence. My main point was to say that it's think it is better to create tickets for what you want, rather than for something else
RE: Do you have a site in production environment with Cassandra? What client do you use?
- Cassandra 0.7 beta1 on virtual Windows Server 2008 64bit machines (8 total). - In-house built C# client for .NET app connecting using Thrift, was worth it to built own client. - 150M transactions/day load and growing. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies.-Original Message- From: Ertio Lew [mailto:ertio...@gmail.com] Sent: Friday, January 14, 2011 19:25 To: user Subject: Do you have a site in production environment with Cassandra? What client do you use? Hey, If you have a site in production environment or considering so, what is the client that you use to interact with Cassandra. I know that there are several clients available out there according to the language you use but I would love to know what clients are being used widely in production environments and are best to work with(support most required features for performance). Also preferably tell about the technology stack for your applications. Any suggestions, comments appreciated ? Thanks Ertio
RE: about the data directory
I have 4 nodes, then I I create one keyspace (such as FOO) with replica factor =1 and insert an data, why I can see the directory of /var/lib/Cassandra/data/FOO in every nodes? As I know, I just have one replica So why do you have installed 4 nodes, not 1? They're for your data to be distributed between 4 nodes with 1 copy on one of them. This is like you have 100% of data and each node will have 25% of the data (random partitioning). Viktor. Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania [cid:signature-logo6784.png]http://www.adform.com/ Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies. inline: signature-logo6784.png
RE: [RELEASE] 0.7.0 (and 0.6.9)
Congratulations!!! Best regards/ Pagarbiai Viktor Jevdokimov Senior Developer Email: viktor.jevdoki...@adform.com Phone: +370 5 212 3063 Fax: +370 5 261 0453 Konstitucijos pr. 23, LT-08105 Vilnius, Lithuania Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the interested recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete or destroy this message and any copies.-Original Message- From: Eric Evans [mailto:eev...@rackspace.com] Sent: Tuesday, January 11, 2011 19:23 To: user@cassandra.apache.org Subject: [RELEASE] 0.7.0 (and 0.6.9) As some of you may already be aware, 0.7.0 has been officially released. You are free to start your upgrades, though not all at once, you'll spoil your supper! I apologize to anyone that might have noticed artifacts published as early as Sunday and were confused by the lack of announcement, I was waiting for an Official ASF Press Release and my timing sucks. https://blogs.apache.org/foundation/entry/the_apache_software_foundation_announces9 There is way too much hotness in 0.7.0 to cover here, so instead I will refer you to the following articles. http://www.rackspacecloud.com/blog/2010/10/27/new-features-in-cassandra-0-7 http://www.riptano.com/blog/whats-new-cassandra-07-secondary-indexes http://www.riptano.com/blog/whats-new-cassandra-07-hadoop-output-cassandra http://www.riptano.com/blog/whats-new-cassandra-07-expiring-columns http://www.riptano.com/blog/whats-new-cassandra-07-live-schema-updates And of course, let's not forget the release notes. http://goo.gl/Bi8LD As usual you can download 0.7.0 from the website: http://cassandra.apache.org/download Users of Debian and derivatives can install from our repository: http://wiki.apache.org/cassandra/DebianPackaging New for 0.7.0, Cassandra is also available from Maven Central (thanks Stephen Connolly). But wait, there's more! If you're not in a hurry to upgrade, we have a new 0.6 release as well, 0.6.9. It's an easy upgrade for anyone running 0.6.8 and contains a number of useful changes (http://goo.gl/6NIPG). The Debian repository has been extended to support an extra version so if you're accustomed to installing 0.6 from our repository, then be sure to change your suite name to 06x in sources.list. For example: deb http://www.apache.org/dist/cassandra/debian 06x main deb-src http://www.apache.org/dist/cassandra/debian 06x main That's it, thanks everyone! -- Eric Evans eev...@rackspace.com
RE: Quorum: killing 1 out of 3 server kills the cluster (?)
With 3 nodes and RF=2 you have 3 key ranges: N1+N2, N2+N3 and N3+N1. Killing N1 you've got only 1 alive range N2+N3 and 2/3 of the range is down for Quorum, which is actually all, so N1+N2 and N3+N1 fails. -Original Message- From: Timo Nentwig [mailto:timo.nent...@toptarif.de] Sent: Thursday, December 09, 2010 6:01 PM To: user@cassandra.apache.org Subject: Re: Quorum: killing 1 out of 3 server kills the cluster (?) On Dec 9, 2010, at 16:50, Daniel Lundin wrote: Quorum is really only useful when RF 2, since the for a quorum to succeed RF/2+1 replicas must be available. 2/2+1==2 and I killed 1 of 3, so... don't get it. This means for RF = 2, consistency levels QUORUM and ALL yield the same result. /d On Thu, Dec 9, 2010 at 4:40 PM, Timo Nentwig timo.nent...@toptarif.de wrote: Hi! I've 3 servers running (0.7rc1) with a replication_factor of 2 and use quorum for writes. But when I shut down one of them UnavailableExceptions are thrown. Why is that? Isn't that the sense of quorum and a fault-tolerant DB that it continues with the remaining 2 nodes and redistributes the data to the broken one as soons as its up again? What may I be doing wrong? thx tcn
RE: Booting Cassandra v0.7.0 on Windows: rename failed
This isn't a first time Cassandra has I/O issues on Windows. I think it's not easy to review source code and eliminate such issues, but would like developers to keep in mind such issues in the future. We're also running a Cassandra cluster on Windows, but 0.7 beta1 (with similar issue, but for Commit Log) and waiting for 0.7 release to use it fully on production. Viktor -Original Message- From: Jonathan Ellis [mailto:jbel...@gmail.com] Sent: Monday, November 29, 2010 5:09 PM To: user Subject: Re: Booting Cassandra v0.7.0 on Windows: rename failed Please report a bug at https://issues.apache.org/jira/browse/CASSANDRA On Mon, Nov 29, 2010 at 2:49 AM, Ramon Rockx r.ro...@asknow.nl wrote: Hi, Recently I downloaded Cassandra v0.7.0 rc1. When I try to run cassandra it ends with the following logging: INFO 09:17:30,044 Enqueuing flush of memtable-locationi...@839514767(643 bytes, 12 operations) INFO 09:17:30,045 Writing memtable-locationi...@839514767(643 bytes, 12 operations) ERROR 09:17:30,233 Fatal exception in thread Thread[FlushWriter:1,5,main] java.io.IOError: java.io.IOException: rename failed of d:\cassandra\data\system\LocationInfo-e-1-Data.db at org.apache.cassandra.io.sstable.SSTableWriter.rename(SSTableWriter.java: 214) at org.apache.cassandra.io.sstable.SSTableWriter.closeAndOpenReader(SSTable Writer.java:184) at org.apache.cassandra.io.sstable.SSTableWriter.closeAndOpenReader(SSTable Writer.java:167) at org.apache.cassandra.db.Memtable.writeSortedContents(Memtable.java:161) at org.apache.cassandra.db.Memtable.access$000(Memtable.java:49) at org.apache.cassandra.db.Memtable$1.runMayThrow(Memtable.java:174) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:30) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecuto r.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.ja va:908) at java.lang.Thread.run(Thread.java:619) Caused by: java.io.IOException: rename failed of d:\cassandra\data\system\LocationInfo-e-1-Data.db at org.apache.cassandra.utils.FBUtilities.renameWithConfirm(FBUtilities.jav a:359) at org.apache.cassandra.io.sstable.SSTableWriter.rename(SSTableWriter.java: 210) ... 12 more Operating system is Windows 7. Tried it also on Windows 2003 server. I only modified a few (necessary) path settings in cassandra.yaml: commitlog_directory: d:/cassandra/commitlog data_file_directories: - d:/cassandra/data saved_caches_directory: d:/cassandra/saved_caches Does anybody know what I'm doing wrong? Regards, Ramon -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com
RE: Preventing an update of a CF row
Nice and simple! -Original Message- From: Oleg Anastasyev [mailto:olega...@gmail.com] Sent: Tuesday, October 19, 2010 9:00 AM To: user@cassandra.apache.org Subject: Re: Preventing an update of a CF row kannan chandrasekaran ckannanck at yahoo.com writes: Hi All,I have a query regarding the insert operation. The insert operation by default inserts an new row or updates an existing row. Is it possible to prevent an update but allow only inserts automatically ( especially when multiple clients are writing to cassandra)? I was wondering if there is any flag in cassandra that will validate this for me automatically ( something like unique key constraint) ? If not, is it non-trivial to implement this ? Any suggestions would be helpful.ThanksKannan Always specify some constant value for timestamp. Only 1st insertion with that timestamp will succeed. Others will be ignored, because will be considered duplicates by cassandra.
RE: Preventing an update of a CF row
Reverse timestamp.
-Original Message-
From: Sylvain Lebresne [mailto:sylv...@yakaz.com]
Sent: Tuesday, October 19, 2010 10:44 AM
To: user@cassandra.apache.org
Subject: Re: Preventing an update of a CF row
Always specify some constant value for timestamp. Only 1st insertion with that
timestamp will succeed. Others will be ignored, because will be considered
duplicates by cassandra.
Well, that's not entirely true. When cassandra 'resolves' two columns
having the
same timestamp, it will compare the values to decide which one to keep
(and it'll
keep the one column whose value is greater for bytes comparison).
Concretely, if you insert Column('foo', 'b', 0) and then Column('foo',
'bar', 0), then
you'll end up with the second column, even though the timestamps are the same
because 'bar' 'b'.
So constant timestamps doesn't work for preventing updates of a given column.
--
Sylvain
RE: 0.7 live schema updates
But you'll loose these settings after Cassandra restart. -Original Message- From: Oleg Anastasyev [mailto:olega...@gmail.com] Sent: Thursday, September 16, 2010 11:21 AM To: user@cassandra.apache.org Subject: Re: 0.7 live schema updates You can change these attrs using JMX interface. Take a look at org.apache.cassandra.tools.NodeProbe setCacheCapacities method.
RE: Cassandra 0.7 logging
We found that on Windows only log4j.properties is working for logging, not log4-server.properties -Original Message- From: Alaa Zubaidi [mailto:alaa.zuba...@pdf.com] Sent: Wednesday, September 08, 2010 7:34 AM To: user@cassandra.apache.org Subject: Re: Cassandra 0.7 logging I did most of the things you said, I will check the rest and double check all. Thanks and Regards, Alaa On 9/7/2010 9:20 PM, Aaron Morton wrote: AFAIK nothing has changed in the logging other than the name of the config file. All the logging is done through log4j. Do not know about the windows install, but using the normal (non package install) on linux the /var/log/cassandra path was not automatically created. It's going to be a config problem on your side. Check the settings again, check all the directories exist, check the user that cassandra is running under has full permissions on the directory, check the root logger is configured to use the rolling file appender (e.g. log4j.rootLogger=INFO,R ) Aaron On 08 Sep, 2010,at 03:42 PM, Alaa Zubaidialaa.zuba...@pdf.com wrote: I modified the log4-server.properties: /# Edit the next line to point to your logs directory log4j.appender.RFile=E:\var\log\cassandra\Cass07\system.log / Cassandra is installed on E: The var\log\cassandra is created on the same place where Cassandra is installed which is (in my case) E However, I am NOT sure that 0.7 is responsible for creating the system.log under E:\var\log\cassandra\ It was previous releases (0.6.5). Thanks Alaa On 9/7/2010 6:42 PM, Aaron Morton wrote: Ah, running on windows Have you included the drive spec in the logging configuration, i.e. is you logging configured to use E:\var\log\cassandra\Cass07\system.log When you say cassandra created /var/log/cassandra/system.log i'ts a bit confusing, what drive are you talking about ? Aaron On 08 Sep, 2010,at 01:22 PM, Alaa Zubaidialaa.zuba...@pdf.com wrote: Thanks Aaron, For some reason /var/log/cassandra/system.log does not have the 0.7 info, it has the Old 0.6.5 info. I modified the log4-server.properties and changed the default location and still did not get anything? I running on Windows by the way, and Cassandra created /var/log/cassandra/system.log and I changed it to: E:\var\log\cassandra\Cass07\system.log Regards, Alaa On 9/7/2010 6:04 PM, Aaron Morton wrote: logging is configured in the conf/log4-server.properties file. The default location is /var/log/cassandra/system.log It's enabled at the INFO level by default, and also logs to the file and stdout by default. Aaron On 08 Sep, 2010,at 12:44 PM, Alaa Zubaidialaa.zuba...@pdf.com wrote: Hi, I are testing 0.7 and I cannot find the system.log file, is there any thing I need to do in order to enable the logging? I read about the changes made to the logging in 0.7 but did not find any thing that needs to be done to enable the logging. Regards, Alaa -- Alaa Zubaidi PDF Solutions, Inc 333 West San Carlos Street, Suite 700 San Jose, CA 95110 USA Tel: 408-283-5639 (or 408-280-7900 x5639) fax: 408-938-6479 email:alaa.zuba...@pdf.com -- Alaa Zubaidi PDF Solutions, Inc. 333 West San Carlos Street, Suite 700 San Jose, CA 95110 USA Tel: 408-283-5639 (or 408-280-7900 x5639) fax: 408-938-6479 email:alaa.zuba...@pdf.com -- Alaa Zubaidi PDF Solutions, Inc. 333 West San Carlos Street, Suite 700 San Jose, CA 95110 USA Tel: 408-283-5639 (or 408-280-7900 x5639) fax: 408-938-6479 email: alaa.zuba...@pdf.com
Cache capacity set with JConsole is lost after restart
Hi, We're not setting cache capacity upon creation of Column Family, since the type and capacity is unknown at that time. By default it = 0. After Column Family has enough data and we could decide on cache type (Row or Key) and capacity, we connect with JConsole and set cache capacity manually on every node. But after Cassandra restart cache capacity is 0 again. How to avoid losing cache capacity after restart? Viktor
RE: Cache capacity set with JConsole is lost after restart
Forgot to mention the version: 0.7 beta 1 -Original Message- From: Edward Capriolo [mailto:edlinuxg...@gmail.com] Sent: Friday, September 03, 2010 4:59 PM To: user@cassandra.apache.org Subject: Re: Cache capacity set with JConsole is lost after restart On Fri, Sep 3, 2010 at 9:22 AM, Viktor Jevdokimov viktor.jevdoki...@adform.com wrote: Hi, We're not setting cache capacity upon creation of Column Family, since the type and capacity is unknown at that time. By default it = 0. After Column Family has enough data and we could decide on cache type (Row or Key) and capacity, we connect with JConsole and set cache capacity manually on every node. But after Cassandra restart cache capacity is 0 again. How to avoid losing cache capacity after restart? Viktor Viktor, I will assume you are using 6.X. In 6.X changes to cache capacity through JMX are NOT saved. Use the KeysCached and RowsCached ColumnFamily Name=Super2 ColumnType=Super CompareWith=UTF8Type CompareSubcolumnsWith=UTF8Type RowsCached=1 KeysCached=111 Be warned the attributes are CaSe SeNSative!
RE: Running Cassandra as a Windows Service
I'm very interested in Windows Service, as x86 as x64 versions. Have you any success to start Cassandra with Procrun alone? Viktor From: Kochheiser,Todd W - TOK-DITT-1 [mailto:twkochhei...@bpa.gov] Sent: Thursday, July 01, 2010 9:49 PM To: 'user@cassandra.apache.org' Subject: RE: Running Cassandra as a Windows Service I've been running it in our development test environments as a Windows Service without any problem. I have not been too sophisticated in my configurations, but have been running some simple two node clusters. At this point nothing has yet caused me any concern. I have been working on a contrib. package for Cassandra and hope to have something submitted for review in the next week or so. It will include everything needed to run Cassandra as a service. In order to make Cassandra work well with Apache's Procrunhttp://commons.apache.org/daemon/procrun.html, I needed to write a simple WindowsService class. In addition to the procrun executables for 32/64 bit platforms and a batch file to install and remove the service, I'll also be including an ant build file and associated unit tests. Todd From: Viktor Jevdokimov [mailto:viktor.jevdoki...@adform.com] Sent: Thursday, July 01, 2010 6:39 AM To: user@cassandra.apache.org Cc: Kochheiser,Todd W - TOK-DITT-1 Subject: RE: Running Cassandra as a Windows Service Hi, Can you share your experience with running Cassandra as a Windows Service? Thank you, Viktor From: Kochheiser,Todd W - TO-DITT1 [mailto:twkochhei...@bpa.gov] Sent: Thursday, June 10, 2010 8:34 PM To: 'user@cassandra.apache.org' Subject: Running Cassandra as a Windows Service For various reasons I am required to deploy systems on Windows. As such, I went looking for information on running Cassandra as a Windows service. I've read some of the user threads regarding running Cassandra as a Windows service, such as this one: http://www.mail-archive.com/user@cassandra.apache.org/msg01656.html I also found the following JIRA issue: https://issues.apache.org/jira/browse/CASSANDRA-292 As it didn't look like anyone has contributed a formal solution and having some experience using Apache's Procrun (http://commons.apache.org/daemon/procrun.html), I decided to go ahead and write a batch script and a simple WindowsService class to accomplish the task. The WindowsService class only makes calls to public methods in CassandraDeamon and is fairly simple. In combination with the batch script, it is very easy to install and remove the service. At this point, I've installed Cassandra as a Windows service on XP (32 bit), Windows 7 (64 bit) and Windows Server 2008 R1/R2 (64 bit). It should work fine on other version of Windows (2K, 2K3). Questions: 1. Has anyone else already done this work? 2. If not, I wouldn't mind sharing the code/script or contributing it back to the project. Is there any interest in this from the Cassandra dev team or the user community? Ideally the WindowsService could be included in the distributed source/binary distributions (perhaps in a contrib area) as well as the batch script and associated procrun executables. Or, perhaps it could be posted to a Cassandra community site (is there one?). Todd
RE: Extremly slow inserts on LAN
We had similar experience. Problem was with TSocket as transport alone: var transport = new TSocket(192.168.0.123, 9160); var protocol = new TBinaryProtocol(transport); var client = new Cassandra.Client(protocol); Using TBufferedTransport helped a lot: var transport = new TBufferedTransport(new TSocket(192.168.0.123, 9160)); var protocol = new TBinaryProtocol(transport); var client = new Cassandra.Client(protocol); Viktor -Original Message- From: Arie Keren [mailto:a...@doubleverify.com] Sent: Monday, May 10, 2010 8:51 AM To: user@cassandra.apache.org Subject: RE: Extremly slow inserts on LAN No - just Windows. So I'm going to do some experiments to isolate the cause: - use java client on windows - use linux server - use java client on linux Thanx -Original Message- From: David Strauss [mailto:da...@fourkitchens.com] Sent: May 09, 2010 5:48 PM To: user@cassandra.apache.org Subject: Re: Extremly slow inserts on LAN From a naive (not caring about Cassandra internals) basis, the first step is to isolate whether the problem is on the client or server side. Have you tried a Linux-based server or a Linux-based client? On 2010-05-09 14:06, Arie Keren wrote: While making our first steps with Cassandra, we experience slow inserts working on LAN. Inserting 7000 keys with 1 column family takes about 10 seconds when Cassandra server running on the same host with the client. But when server runs on a different host on LAN, the same inserts take more than 10 (!) minutes. In both cases Cassandra server contains a single node. We use Cassandra version 0.6.0 running on Windows server 2008. The client is .NET c# application. -- David Strauss | da...@fourkitchens.com Four Kitchens | http://fourkitchens.com | +1 512 454 6659 [office] | +1 512 870 8453 [direct] __ Information from ESET NOD32 Antivirus, version of virus signature database 4628 (20091122) __ The message was checked by ESET NOD32 Antivirus. http://www.eset.com
RE: Cassandra on Windows network latency
Yes, we have already figured that out :) Thanks! -Original Message- From: Carlos Alvarez [mailto:cbalva...@gmail.com] Sent: Thursday, April 29, 2010 4:03 PM To: user@cassandra.apache.org Subject: Re: Cassandra on Windows network latency Are you using TSocket in the client?. If yes, use TbufferedTransport instead. Carlos On 4/29/10, Viktor Jevdokimov viktor.jevdoki...@adform.com wrote: Thrift C# sources, thrift generated Cassandra sources, test app built with C#. Simple connect/write/read operations. No pooling or anything else. From: Heath Oderman [mailto:he...@526valley.com] Sent: Thursday, April 29, 2010 2:17 PM To: user@cassandra.apache.org Subject: Re: Cassandra on Windows network latency I learned the hard way, that running py_stress in the src/contrib directory is a great way to test what kind of speeds you are really getting. What tools / client are you using to test to get the 200ms number? stu On Thu, Apr 29, 2010 at 7:12 AM, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: Hi all, We have installed Cassandra on Windows and found that with any number of Cassandra (single, or 3 node cluster) on Windows Vista or Windows Server 2008, 32 or 64 bit, with any load or number of requests we, have: When client and server are on the same machine, connect/read/write latencies ~0-1ms When client on another machine, same network, on the same switch, connection latency 0-1ms (as a ping), read/write latencies =200ms. What causes 200ms latency accessing Cassandra on Windows through network? Does anybody experience such behavior? Cassandra 0.6.1 Java SE 6 u20 Best regards, Viktor -- Sent from my mobile device Tal vez hubo un error en la grafía. O en la articulación del Sacro Nombre.
Primary and Backup clusters
Hello, Our system (not Cassandra) have backup cluster in different datacenter in case of primary cluster unavailability or for software upgrades. 100% of traffic goes to primary cluster. We switch 100% traffic to backup cluster in case above for a short time, then when issues are resolved, traffic is switched back to primary. We'd like to have primary and backup Cassandra clusters in different datacenters for the same reasons. We do not want to have a high traffic between primary and backup datacenters. Now the questions: 1. How to sync Cassandra clusters (backup-primary) with minimal traffic? 2. How to configure Cassandra in such case? Thanks, Viktor
Cassandra on Windows network latency
Hi all, We have installed Cassandra on Windows and found that with any number of Cassandra (single, or 3 node cluster) on Windows Vista or Windows Server 2008, 32 or 64 bit, with any load or number of requests we, have: When client and server are on the same machine, connect/read/write latencies ~0-1ms When client on another machine, same network, on the same switch, connection latency 0-1ms (as a ping), read/write latencies =200ms. What causes 200ms latency accessing Cassandra on Windows through network? Does anybody experience such behavior? Cassandra 0.6.1 Java SE 6 u20 Best regards, Viktor
RE: Cassandra on Windows network latency
Thrift C# sources, thrift generated Cassandra sources, test app built with C#. Simple connect/write/read operations. No pooling or anything else. From: Heath Oderman [mailto:he...@526valley.com] Sent: Thursday, April 29, 2010 2:17 PM To: user@cassandra.apache.org Subject: Re: Cassandra on Windows network latency I learned the hard way, that running py_stress in the src/contrib directory is a great way to test what kind of speeds you are really getting. What tools / client are you using to test to get the 200ms number? stu On Thu, Apr 29, 2010 at 7:12 AM, Viktor Jevdokimov viktor.jevdoki...@adform.commailto:viktor.jevdoki...@adform.com wrote: Hi all, We have installed Cassandra on Windows and found that with any number of Cassandra (single, or 3 node cluster) on Windows Vista or Windows Server 2008, 32 or 64 bit, with any load or number of requests we, have: When client and server are on the same machine, connect/read/write latencies ~0-1ms When client on another machine, same network, on the same switch, connection latency 0-1ms (as a ping), read/write latencies =200ms. What causes 200ms latency accessing Cassandra on Windows through network? Does anybody experience such behavior? Cassandra 0.6.1 Java SE 6 u20 Best regards, Viktor
