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https://issues.apache.org/jira/browse/BOOKKEEPER-563?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13694060#comment-13694060
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Ivan Kelly commented on BOOKKEEPER-563:
---------------------------------------
{quote}
there are bunch of os doesn't support posix_fadvise.
http://www.gnu.org/software/gnulib/manual/html_node/posix_005ffadvise.html
it would fail tests on mac if we don't have os checking.
http://mail-archives.apache.org/mod_mbox/cassandra-user/201104.mbox/%[email protected]%3E
{quote}
Indeed. Anything not supporting "_XOPEN_SOURCE >= 600 || _POSIX_C_SOURCE >=
200112L" wont have it. But whether it has it or not is easy to test without
having to revert to checking the OS. If you call posix_fadvise on a system that
doesn't have it, you'll get
{code}
Exception in thread "main" java.lang.UnsatisfiedLinkError: Error looking up
function 'posix_fadvise': java: undefined symbol: posix_fadvise
at com.sun.jna.Function.<init>(Function.java:179)
at com.sun.jna.NativeLibrary.getFunction(NativeLibrary.java:344)
at com.sun.jna.NativeLibrary.getFunction(NativeLibrary.java:324)
at com.sun.jna.Native.register(Native.java:1341)
at com.sun.jna.Native.register(Native.java:1018)
at testjna.main(testjna.java:16)
{code}
which can be caught.
{code}
if (hasFadvise) {
try {
posix_fadvise(sysFileDesc, offset, len, POSIX_FADV_DONTNEED);
} catch (UnsatisfiedLinkError ule) {
LOG.info("posix_fadvise not found");
hasFadvise = false;
}
}
{code}
Having said that, I don't think this is worth blocking the patch for, so +1 on
the patch. We can create another JIRA to resolve this issue. Also, I think the
-1 for the tests is fine in this case.
> Avoid Journal polluting page cache
> ----------------------------------
>
> Key: BOOKKEEPER-563
> URL: https://issues.apache.org/jira/browse/BOOKKEEPER-563
> Project: Bookkeeper
> Issue Type: Improvement
> Reporter: Sijie Guo
> Assignee: Robin Dhamankar
> Fix For: 4.3.0
>
> Attachments: BOOKKEEPER-563.diff, BOOKKEEPER-563.reverse.diff,
> BOOKKEEPER-563.reverse.diff
>
>
> writing data into journal which force the data in os buffer cache being used
> for hot reads, which could have negative affect on performance.
> similar solution is as CASSANDRA-1470.
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