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Jonathan Ellis commented on CASSANDRA-2749: ------------------------------------------- bq. we cannot stream between two nodes, one using separate cf directory I don't see any reason to continue to support the old-style directory layout. That adds complexity (operationally as well as in the code) for no benefit that I can think of. I think we should migrate from old layout to new on the first startup under 1.1. bq. regarding keyspaces in file names, sure, why not, guess having a header with this info in the file is out of the question, then the only meta data we have is the file name, right? A problem could be if we want to do CASSANDRA-1983 later, that would increase the file name length even more I'm on the fence here -- on the one hand having ks + cf in the filename simplifies some things. On the other hand, we allow arbitrary-length KS + CF names (up to 64K iirc) so UUID aside we're already in trouble on ext3/ext4, xfs, and ntfs, which all support max filename length of ~256. I'm starting to think we should move these into the metadata component instead of the filename. > fine-grained control over data directories > ------------------------------------------ > > Key: CASSANDRA-2749 > URL: https://issues.apache.org/jira/browse/CASSANDRA-2749 > Project: Cassandra > Issue Type: New Feature > Components: Core > Reporter: Jonathan Ellis > Priority: Minor > Fix For: 1.1 > > Attachments: > 0001-Make-it-possible-to-put-column-families-in-subdirect.patch, > 0001-add-new-directory-layout.patch, > 0001-non-backwards-compatible-patch-for-2749-putting-cfs-.patch.gz, > 0002-fix-unit-tests.patch, 2749.tar.gz, 2749_backwards_compatible_v1.patch, > 2749_backwards_compatible_v2.patch, 2749_backwards_compatible_v3.patch, > 2749_backwards_compatible_v4.patch, > 2749_backwards_compatible_v4_rebase1.patch, 2749_not_backwards.tar.gz, > 2749_proper.tar.gz > > > Currently Cassandra supports multiple data directories but no way to control > what sstables are placed where. Particularly for systems with mixed SSDs and > rotational disks, it would be nice to pin frequently accessed columnfamilies > to the SSDs. > Postgresql does this with tablespaces > (http://www.postgresql.org/docs/9.0/static/manage-ag-tablespaces.html) but we > should probably avoid using that name because of confusing similarity to > "keyspaces." -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa For more information on JIRA, see: http://www.atlassian.com/software/jira