I'm +1 to remove the fdatasync or any other
sync method.
Log must be run with low priority....
If Dan agree, I'll remove the datasync. :)
-
Henri Gomez ___[_]____
EMAIL : [EMAIL PROTECTED] (. .)
PGP KEY : 697ECEDD ...oOOo..(_)..oOOo...
PGP Fingerprint : 9DF8 1EA8 ED53 2F39 DC9B 904A 364F 80E6
>-----Original Message-----
>From: Rainer Jung [mailto:[EMAIL PROTECTED]]
>Sent: Friday, April 20, 2001 12:33 PM
>To: [EMAIL PROTECTED]
>Subject: RE: Tomcat mod_jk very slow if used with apache
>
>
>Hello Henri, hello Thomas,
>
>The problem comes from the call to fdatasync in the logging
>code of mod_jk.
>I already mentioned this to Dan Milstein. It should really be
>checked, if
>that way of flushing to the physical disk (and not only to the
>file system
>cache which should be enough) is really needed.
>
>The problem becomed more important due to the fact, that the actual
>production release incorrectly documents the existence of a log level
>"warn". In 3.2.1 this does not exist. The header file for the logging
>declares only:
>
>#define JK_LOG_DEBUG_LEVEL 0
>#define JK_LOG_INFO_LEVEL 1
>#define JK_LOG_ERROR_LEVEL 2
>#define JK_LOG_EMERG_LEVEL 3
>
>#define JK_LOG_DEBUG_VERB "debug"
>#define JK_LOG_INFO_VERB "info"
>#define JK_LOG_ERROR_VERB "error"
>#define JK_LOG_EMERG_VERB "emerg"
>
>and if you use any undeclared log level (as e.g. warn) the code falls
>through to "debug". So using warn you actually produce tons of debug
>output, each line calling fdatasync to flush to disk.
>
>We had the same problem on the first day of a heavy load
>production system
>and had some hard hours to find out.
>
>I think the second point (incorrect log level "warn") is
>corrected in the
>next release (by changing documentation and default - not
>code), the first
>thing, throwing out fdatasync - should still be done.
>
>Greetings,
>
>Rainer Jung
>
>
>At 10:54 20.04.01 , you wrote:
>>Could you be more explicit.
>>
>>OS, mod_jk version, tomcat version, apache version ....
>>
>>Thanks
>>
>>-
>>Henri Gomez ___[_]____
>>EMAIL : [EMAIL PROTECTED] (. .)
>>PGP KEY : 697ECEDD ...oOOo..(_)..oOOo...
>>PGP Fingerprint : 9DF8 1EA8 ED53 2F39 DC9B 904A 364F 80E6
>>
>>
>>
>> >-----Original Message-----
>> >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
>> >Sent: Friday, April 20, 2001 10:52 AM
>> >To: [EMAIL PROTECTED]
>> >Subject: Tomcat mod_jk very slow if used with apache
>> >
>> >
>> >I encountered the following problem:
>> >Tomcat was about 20 times slower if the access went via
>> >apache, compared
>> >to a direct access.
>> >
>> >The solution was the following: I had to put the loglevel of
>> >mod_jk to error
>> >instead of warn(as proposed).
>> >
>> >httpd.conf:
>> >JkLogLevel error
>> >
>> >
>> >Mod_jk does not seem to be a quick logger.
>> >
>> >This is the logoutput for out simple request if
>> >JkLogLevel warn:
>> >
>> >[jk_uri_worker_map.c (344)]: Into
>> >jk_uri_worker_map_t::map_uri_to_worker
>> >[jk_uri_worker_map.c (406)]:
>> >jk_uri_worker_map_t::map_uri_to_worker, Found
>> >a match loadbalancer
>> >[jk_worker.c (123)]: Into wc_get_worker_for_name loadbalancer
>> >[jk_worker.c (127)]: wc_get_worker_for_name, done found a worker
>> >[jk_lb_worker.c (471)]: Into jk_worker_t::get_endpoint
>> >[jk_lb_worker.c (300)]: Into jk_endpoint_t::service
>> >[jk_ajp13_worker.c (651)]: Into jk_worker_t::get_endpoint
>> >[jk_ajp13_worker.c (536)]: Into jk_endpoint_t::service
>> >[jk_ajp13.c (346)]: Into ajp13_marshal_into_msgb
>> >[jk_ajp13.c (480)]: ajp13_marshal_into_msgb - Done
>> >[jk_connect.c (108)]: Into jk_open_socket
>> >[jk_connect.c (115)]: jk_open_socket, try to connect socket = 8
>> >[jk_connect.c (124)]: jk_open_socket, after connect ret = 0
>> >[jk_connect.c (132)]: jk_open_socket, set TCP_NODELAY to on
>> >[jk_connect.c (140)]: jk_open_socket, return, sd = 8
>> >[jk_ajp13_worker.c (166)]: In
>> >jk_endpoint_t::connect_to_tomcat, connected
>> >sd = 8
>> >[jk_ajp13.c (527)]: ajp13_unmarshal_response: status = 200
>> >[jk_ajp13.c (534)]: ajp13_unmarshal_response: Number of
>headers is = 1
>> >[jk_ajp13.c (576)]: ajp13_unmarshal_response: Header[0]
>> >[Content-Type] =
>> >[text/html]
>> >[jk_ajp13_worker.c (489)]: Into jk_endpoint_t::done
>> >[jk_lb_worker.c (378)]: Into jk_endpoint_t::done
>> >
>> >
>> >
>> >Greethings, Thomas
>> >
>> >
>> >
>> >
>> >________________________________________
>> >Dreaming of a Swiss Account? Get it here:
http://freemail.swissinfo.org
> >
