[jira] [Updated] (CASSANDRA-6794) Optimise slab allocator to enable higher number of column families
[ https://issues.apache.org/jira/browse/CASSANDRA-6794?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] C. Scott Andreas updated CASSANDRA-6794: Component/s: Core > Optimise slab allocator to enable higher number of column families > -- > > Key: CASSANDRA-6794 > URL: https://issues.apache.org/jira/browse/CASSANDRA-6794 > Project: Cassandra > Issue Type: New Feature > Components: Core >Reporter: Jeremy Hanna >Priority: Minor > > Currently the slab allocator allocates 1MB per column family. This has been > very beneficial for gc efficiency. However, it makes it more difficult to > have large numbers of column families. > It would be preferable to have a more intelligent way to allocate slabs so > that there is more flexibility between slab allocator and non-slab allocator > behaviour. > A simple first step is to ramp up size of slabs from small (say 8KB) when > empty, to 1MB after a few slabs. -- This message was sent by Atlassian JIRA (v7.6.3#76005) - To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org For additional commands, e-mail: commits-h...@cassandra.apache.org
[jira] [Updated] (CASSANDRA-6794) Optimise slab allocator to enable higher number of column families
[ https://issues.apache.org/jira/browse/CASSANDRA-6794?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Jonathan Ellis updated CASSANDRA-6794: -- Priority: Minor (was: Major) Issue Type: New Feature (was: Improvement) FTR, I still think "large numbers of CFs" is an antipattern that we don't want to encourage. Remember, the smaller the unit of a flush is, the closer we approach doing random i/o on flush and compaction. > Optimise slab allocator to enable higher number of column families > -- > > Key: CASSANDRA-6794 > URL: https://issues.apache.org/jira/browse/CASSANDRA-6794 > Project: Cassandra > Issue Type: New Feature > Components: Core >Reporter: Jeremy Hanna >Assignee: Benedict >Priority: Minor > > Currently the slab allocator allocates 1MB per column family. This has been > very beneficial for gc efficiency. However, it makes it more difficult to > have large numbers of column families. > It would be preferable to have a more intelligent way to allocate slabs so > that there is more flexibility between slab allocator and non-slab allocator > behaviour. > A simple first step is to ramp up size of slabs from small (say 8KB) when > empty, to 1MB after a few slabs. -- This message was sent by Atlassian JIRA (v6.2#6252)
[jira] [Updated] (CASSANDRA-6794) Optimise slab allocator to enable higher number of column families
[ https://issues.apache.org/jira/browse/CASSANDRA-6794?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Jonathan Ellis updated CASSANDRA-6794: -- Assignee: (was: Benedict) > Optimise slab allocator to enable higher number of column families > -- > > Key: CASSANDRA-6794 > URL: https://issues.apache.org/jira/browse/CASSANDRA-6794 > Project: Cassandra > Issue Type: New Feature > Components: Core >Reporter: Jeremy Hanna >Priority: Minor > > Currently the slab allocator allocates 1MB per column family. This has been > very beneficial for gc efficiency. However, it makes it more difficult to > have large numbers of column families. > It would be preferable to have a more intelligent way to allocate slabs so > that there is more flexibility between slab allocator and non-slab allocator > behaviour. > A simple first step is to ramp up size of slabs from small (say 8KB) when > empty, to 1MB after a few slabs. -- This message was sent by Atlassian JIRA (v6.2#6252)
