On 7/17/2013 2:57 PM, Christopher Schultz wrote:
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
Jerry,
On 7/17/13 3:30 PM, Jerry Lampi wrote:
On 7/17/2013 2:28 PM, Christopher Schultz wrote: Jerry,
On 7/17/13 3:06 PM, Jerry Lampi wrote:
Good news. I previously reported that sendFile was not
enabled.
As stated below by folks more knowledgeable than I, sendFile
is enabled by default.
I added this line to my server.xml file Connector:
useSendfile="false" and now every page element loads very
quickly. Problem solved.
That's kind of what I was hoping. Honestly, sendFile *should* be
enabled as it should be more efficient, but something is obviously
going wrong.
So it appears that sendFile became broken (at least in my
USS implementation) in version 6.0.36 and beyond.
Should I open an issue for this? In 6.0.35, sendFile seemed
fine, in 6.0.36 and beyond (including 7.x), it is not fine.
Are you always using the same JVM version when testing these
against one another?
Yes. Same JVM. I had another idea. I wonder if tomcat 6.0.35
and below were never REALLY asking for sendFile? That would mean
that the sendFile implementation on the IBM USS mainframe is
faulty, but was not being exercised by tomcat until 6.0.36 and
beyond. I find that possible, as we have had to debug other
issues on that platform.
The only related issue I see in the changelog for 6.0.36 is:
https://issues.apache.org/bugzilla/show_bug.cgi?id=52858
Following 52858 led me to
https://issues.apache.org/bugzilla/show_bug.cgi?id=53138.
It appears that this exact change:
http://svn.apache.org/viewvc/tomcat/tc6.0.x/trunk/java/org/apache/tomcat/util/net/NioEndpoint.java?r1=1372035&r2=1372034&pathrev=1372035
re-activated sendFile on 6.0.36. This seems to have caused slow
(inefficient) code to be run on the IBM USS Mainframe. Specifically, the
line that was commented out:
//unreg(sk,attachment);//only do this if we do process send file on a separate
thread
Now is not:
unreg(sk, attachment, sk.readyOps());
So this issue's description may be summarized better as "The
implementation of sendFile on the IBM USS Mainframe JVM is slow and
inefficient".
I am pretty happy with that answer.
Jerry
Since the file-fetches seem to take a really long time, would you be
able to get a few thread dumps during those times? It might point to
what operation is stalling.
- -chris
-----BEGIN PGP SIGNATURE-----
Version: GnuPG/MacGPG2 v2.0.17 (Darwin)
Comment: GPGTools - http://gpgtools.org
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/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=nyis
-----END PGP SIGNATURE-----
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org
