incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Hiller, Dean" <Dean.Hil...@nrel.gov>
Subject should I file a bug report on this or is this normal?
Date Wed, 06 Mar 2013 14:40:57 GMT
I ran a pretty solid QA test(cleaned data from scratch) on version 1.2.2

My test was as so

 1.  Start up 4 node cassandra cluster
 2.  Populate with initial test data (no other data is added to system after this point!!!)
 3.  Run nodetool drain on every node(move stuff from commit log to sstables)
 4.  Stop and start cassandra cluster to have it running again
 5.  Get size of nreldata CF folder is 128kB
 6.  Go to node 3, run snapshot and mv snapshots directory OUT of nreldata
 7.  Get size of nreldata CF folder is 128kB
 8.  On node 3, run nodetool drain
 9.  Get size of nreldataCF folder is still 128kB
 10. Stop cassandra node
 11. Rm <keyspace>/nreldata/*.db
 12. Size of nreldata CF is 8kb(odd of an empty folder but ok)
 13. Start cassandra
 14. Nodetool repair databus5 nreldata
 15. Size of nreldata is now 220K ….it has exploded in size!!!!!!

I ran this QA test as we see data size explosion in production as well(I can't be 100% sure
if this is the same thing though as above is such a small data set).  Would leveled compaction
be a bit more stable in terms of size ratios and such.

QUESTIONS

 1.  Why is the bloomfilter for level 5 a total of 3856 bytes for 29118(large to small) bytes
of data while in the initial data it was 2192 bytes for 43038(small to large) bytes of data?
 2.  Why is there 3 levels?  With such a small set of data, I would think it would flush one
data file like the original data but instead there is 3 files.

My files after repair have levels 5, 6, and 7.  My files before deletion of the CF have just
level 1.  After repair files are
-rw-rw-r--.  1 cassandra cassandra    54 Mar  6 07:18 databus5-nreldata-ib-5-CompressionInfo.db
-rw-rw-r--.  1 cassandra cassandra 29118 Mar  6 07:18 databus5-nreldata-ib-5-Data.db
-rw-rw-r--.  1 cassandra cassandra  3856 Mar  6 07:18 databus5-nreldata-ib-5-Filter.db
-rw-rw-r--.  1 cassandra cassandra 37000 Mar  6 07:18 databus5-nreldata-ib-5-Index.db
-rw-rw-r--.  1 cassandra cassandra  4772 Mar  6 07:18 databus5-nreldata-ib-5-Statistics.db
-rw-rw-r--.  1 cassandra cassandra   383 Mar  6 07:18 databus5-nreldata-ib-5-Summary.db
-rw-rw-r--.  1 cassandra cassandra    79 Mar  6 07:18 databus5-nreldata-ib-5-TOC.txt
-rw-rw-r--.  1 cassandra cassandra    46 Mar  6 07:18 databus5-nreldata-ib-6-CompressionInfo.db
-rw-rw-r--.  1 cassandra cassandra 14271 Mar  6 07:18 databus5-nreldata-ib-6-Data.db
-rw-rw-r--.  1 cassandra cassandra   816 Mar  6 07:18 databus5-nreldata-ib-6-Filter.db
-rw-rw-r--.  1 cassandra cassandra 18248 Mar  6 07:18 databus5-nreldata-ib-6-Index.db
-rw-rw-r--.  1 cassandra cassandra  4756 Mar  6 07:18 databus5-nreldata-ib-6-Statistics.db
-rw-rw-r--.  1 cassandra cassandra   230 Mar  6 07:18 databus5-nreldata-ib-6-Summary.db
-rw-rw-r--.  1 cassandra cassandra    79 Mar  6 07:18 databus5-nreldata-ib-6-TOC.txt
-rw-rw-r--.  1 cassandra cassandra    46 Mar  6 07:18 databus5-nreldata-ib-7-CompressionInfo.db
-rw-rw-r--.  1 cassandra cassandra 14271 Mar  6 07:18 databus5-nreldata-ib-7-Data.db
-rw-rw-r--.  1 cassandra cassandra   816 Mar  6 07:18 databus5-nreldata-ib-7-Filter.db
-rw-rw-r--.  1 cassandra cassandra 18248 Mar  6 07:18 databus5-nreldata-ib-7-Index.db
-rw-rw-r--.  1 cassandra cassandra  4756 Mar  6 07:18 databus5-nreldata-ib-7-Statistics.db
-rw-rw-r--.  1 cassandra cassandra   230 Mar  6 07:18 databus5-nreldata-ib-7-Summary.db
-rw-rw-r--.  1 cassandra cassandra    79 Mar  6 07:18 databus5-nreldata-ib-7-TOC.txt

Before repair files(from my moved snapshot as I moved it out of the directory so cassandra
no longer had it)….
-rw-rw-r--. 1 cassandra cassandra    62 Mar  6 07:11 databus5-nreldata-ib-1-CompressionInfo.db
-rw-rw-r--. 1 cassandra cassandra 43038 Mar  6 07:11 databus5-nreldata-ib-1-Data.db
-rw-rw-r--. 1 cassandra cassandra  2192 Mar  6 07:11 databus5-nreldata-ib-1-Filter.db
-rw-rw-r--. 1 cassandra cassandra 55248 Mar  6 07:11 databus5-nreldata-ib-1-Index.db
-rw-rw-r--. 1 cassandra cassandra  4756 Mar  6 07:11 databus5-nreldata-ib-1-Statistics.db
-rw-rw-r--. 1 cassandra cassandra   499 Mar  6 07:11 databus5-nreldata-ib-1-Summary.db
-rw-rw-r--. 1 cassandra cassandra    79 Mar  6 07:11 databus5-nreldata-ib-1-TOC.txt

Thanks,
Dean


Mime
View raw message