tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Mike Wertheim ...@hyperreal.org>
Subject Re: increase in file descriptor use from Tomcat 7.0.21 to 7.0.23
Date Tue, 29 Nov 2011 20:07:49 GMT
An update on the situation... The Tomcat 7.0.23 servers tend to blow
up (refusing to accept connections), which the Tomcat 7.0.21 servers
didn't do.  So I've downgraded all of the servers except one to
7.0.21.  I'm keeping one of them at 7.0.23 in order to try to
troubleshoot this problem.

I'm not sure if the following data answers your question, but here are
some raw numbers.

For one of the older Tomcat servers (7.0.21):
Number of open file descriptors according to "ls -l /proc/4501/fd | wc
-l": 13650
Number of those file descriptors that have filename with "socket": 8845 (65%)
Number of those file descriptors that have filename with "eventpoll": 4782 (35%)
Number of active connections according to "netstat -nat": 18664
Number of active connections labeled as ESTABLISHED by netstat: 8727 (47%)
Number of active connections labeled as TIME_WAIT by netstat: 7638 (41%)
Number of active connections labeled as LAST_ACK by netstat: 140 (< 1%)
Number of active connections labeled as CLOSE_WAIT by netstat: 252 (1%)
Number of active connections labeled as FIN_WAIT1 by netstat: 302 (1%)
Number of active connections labeled as FIN_WAIT2 by netstat: 1347 (7%)

For the newer Tomcat server (7.0.23):
Number of open file descriptors according to "ls -l /proc/1648/fd | wc
-l": 19478
Number of those file descriptors that have filename with "socket": 13783 (40%)
Number of those file descriptors that have filename with "eventpoll": 5579 (29%)
Number of active connections according to "netstat -nat": 10865
Number of active connections labeled as ESTABLISHED by netstat: 5772 (54%)
Number of active connections labeled as TIME_WAIT by netstat: 3205 (30%)
Number of active connections labeled as LAST_ACK by netstat: 106 (1%)
Number of active connections labeled as CLOSE_WAIT by netstat: 794 (7%)
Number of active connections labeled as FIN_WAIT1 by netstat: 218 (2%)
Number of active connections labeled as FIN_WAIT2 by netstat: 548 (5%)

Oddly, the newer Tomcat server has more open file descriptors but
fewer active connections.

Does this info help?  Is there anything else I can tell you?

Any idea in what changed between 7.0.21 and 7.0.23 that could account for this?

Thanks!
Mike


On Tue, Nov 29, 2011 at 12:35 AM, Pid * <pid@pidster.com> wrote:
> On 29 Nov 2011, at 01:05, Mike Wertheim <mw@hyperreal.org> wrote:
>
>> I have a web app that has been running on Tomcat 7.0.21 with APR 1.4.2
>> and Tomcat Native 1.1.20 on 64-bit Java 1.6.0.23 on CentOS Linux.
>>
>> I upgraded half of my servers to Tomcat 7.0.23 and left the other half
>> at 7.0.21.  I copied the modified server.xml, context.xml and web.xml
>> files from the 7.0.21 directories to the 7.0.23 directories, so the
>> configurations are identical.
>>
>> The 7.0.21 servers have on average about 10000 file descriptors open.
>> The 7.0.23 servers have on average about 15000 file descriptors open.
>> These numbers are what I get from running this shell command: ls -l
>> /proc/[pid]/fd | wc -l
>>
>> All of the servers are getting about the same amount of traffic.  The
>> only difference is the Tomcat version.
>>
>> Can anyone explain why Tomcat 7.0.23 would have 50% more file descriptors open?
>
> Can you tell what they are opened on?
>
> What is the number of active connections to those servers?
>
>
> p
>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
>> For additional commands, e-mail: users-help@tomcat.apache.org
>>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>

---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
For additional commands, e-mail: users-help@tomcat.apache.org


Mime
View raw message