[ https://issues.apache.org/jira/browse/IMPALA-8542?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16866820#comment-16866820 ]
ASF subversion and git services commented on IMPALA-8542: --------------------------------------------------------- Commit f4ef9ca87352406cc7a484e90ed1d1d702745810 in impala's branch refs/heads/master from Todd Lipcon [ https://gitbox.apache.org/repos/asf?p=impala.git;h=f4ef9ca ] IMPALA-8542. Add an access trace for the data cache This adds a relatively simple JSON-formatted access trace for the data cache feature. Each partition stores a trace file named 'trace.txt', with each line representing a hit, miss, or store into the cache. The trace is collected using the kudu::AsyncLogger class which handles buffering and deferring the actual IO to a background thread. By default, the full cache key info is written to the trace (including the file paths), but a flag can enable anonymization (128-bit city-hashing) of the file names in case any user would like to capture a trace to be shared publically without divulging their table names. Change-Id: I2302c19abb5db19f1d3d1cd727a82977a9e2ba9c Reviewed-on: http://gerrit.cloudera.org:8080/13425 Tested-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com> Reviewed-by: Michael Ho <k...@cloudera.com> > Access trace collection for data cache > -------------------------------------- > > Key: IMPALA-8542 > URL: https://issues.apache.org/jira/browse/IMPALA-8542 > Project: IMPALA > Issue Type: Improvement > Components: Backend > Reporter: Todd Lipcon > Assignee: Todd Lipcon > Priority: Major > Fix For: Impala 3.3.0 > > > Now that we have a remote-read data cache, it would be useful to log an > access trace. The trace can be then fed back into various cache policy > simulators to compare the relative performance, and do "what if" analysis > (how would hit rate react with larger/smaller capacities) -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org