Re: Commit log size vs memtable total size

2016-03-01 Thread Vlad
Tyler, thanks for explanation! So commit segment can contain both data from flushed table A and non-flushed table B.How is it replayed on start up? Does C* skip portions belonging to table A that already were written to SSTable? Regards, Vlad On Tuesday, March 1, 2016 11:37 PM, Tyler Hobbs

Re: Commit log size vs memtable total size

2016-03-01 Thread Jack Krupansky
It would be nice to get this info into the doc or at least a blog post. -- Jack Krupansky On Tue, Mar 1, 2016 at 4:37 PM, Tyler Hobbs wrote: > > On Tue, Mar 1, 2016 at 6:13 AM, Vlad wrote: > >> So commit log can't keep more than memtable size, why is difference in >> commit log and memtables s

Re: Commit log size vs memtable total size

2016-03-01 Thread Tyler Hobbs
On Tue, Mar 1, 2016 at 6:13 AM, Vlad wrote: > So commit log can't keep more than memtable size, why is difference in > commit log and memtables sizes? In order to purge a commitlog segment, *all* memtables that contain data from that segment must be flushed to disk. Suppose you have two tables

Commit log size vs memtable total size

2016-03-01 Thread Vlad
Hi,there are following parameters in casansdra.yaml: memtable_total_space_in_mb (1/4 of heap, e.g. 512MB)- Specifies the total memory used for all memtables on a node. commitlog_total_space_in_mb (8GB) - Total space used for commit logs. If the used space goes above this value, Cassandra rounds u