hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Andrew Purtell (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-13142) [PERF] Reuse the IPCUtil#buildCellBlock buffer
Date Sat, 07 Mar 2015 16:49:39 GMT

    [ https://issues.apache.org/jira/browse/HBASE-13142?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14351690#comment-14351690
] 

Andrew Purtell commented on HBASE-13142:
----------------------------------------

With this patch applied TestMetaScanner times out consistently. 
{noformat}
Tests run: 2, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 92.72 sec <<< FAILURE!
- in org.apache.hadoop.hbase.client.TestMetaScanner
testConcurrentMetaScannerAndCatalogJanitor(org.apache.hadoop.hbase.client.TestMetaScanner)
 Time elapsed: 85.416 sec  <<< ERROR!
org.apache.hadoop.hbase.client.ScannerTimeoutException: 60334ms passed since the last invocation,
timeout is currently set to 60000
Caused by: org.apache.hadoop.hbase.ipc.RemoteWithExtrasException: org.apache.hadoop.hbase.UnknownScannerException:
Name: 372, already closed?
{noformat}
Odd, but there it is.

> [PERF] Reuse the IPCUtil#buildCellBlock buffer
> ----------------------------------------------
>
>                 Key: HBASE-13142
>                 URL: https://issues.apache.org/jira/browse/HBASE-13142
>             Project: HBase
>          Issue Type: Improvement
>          Components: Performance
>            Reporter: stack
>            Assignee: stack
>              Labels: beginner
>             Fix For: 2.0.0, 1.1.0
>
>         Attachments: 13142.txt, 13142v2.txt, 13142v3.txt, 13142v5.0.98.txt, 13142v5.txt,
13142v5.txt, buffers.svg, clean.svg, gc.png, gc_time_spent.png, hits.png, net.png, traces.2.svg,
traces.svg
>
>
> Running some scan profiling, flight recorder was mildly fingering resize of the buffer
allocated in IPCUtil#buildCellBlock as a point of contention.  It was half-hearted blaming
it for a few hundreds of ms over a five minute sampling with a few tens of instances showing.
> I tried then w/ flamegraph/lightweight profiler and this reported the buffer allocations
taking 22% of our total CPU. See attachment trace.svg.
> I enabled TRACE-level logging on org.apache.hadoop.hbase.ipc.IPCUtil and indeed every
allocation was doing a resize from initial allocation of 16k -- the default up to 220k (this
test returns ten randomly sized rows zipfian sized between 0 and 8k).
> Upping the allocation to 220k meant we now avoided the resize but the initial allocation
was now blamed for 10% of allocations (see trace.2.svg attached).
> Lets do buffer reuse.  Will save a bunch of allocation and CPU.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message