Hi All, I have two servers, one is centos 4.3 (new) and other is rh9 (old). Both of them run mysql as the primary database server. I installed mysql via the rpms available in mysql.com downloads. Recently when i do "pstree", i noticed that RH9 server shows many mysql children while centos shows only one. Here is the pstree result. (Both of them runs the same version of mysql) server A (RH9 , MySQL-server-4.1.19-0.glibc23 ) --------------------------------------------------------------------- ??mysqld_safe???mysqld???mysqld???13*[mysqld] and server B (CentOS 4.3 , MySQL-server-4.1.19-0.glibc23 ) --------------------------------------------------------------------- ??mysqld_safe???mysqld my question is, why mysql is showing one process in centos?. I use same my.cnf in both servers. So i believe it is not a config issue. I believe someone can explain it to me. Regards, Renjith Rajan
Renjith Rajan wrote:> Hi All, > > I have two servers, one is centos 4.3 (new) and other is rh9 (old). Both of > them run mysql as the primary database server. I installed mysql via the rpms > available in mysql.com downloads. > > Recently when i do "pstree", i noticed that RH9 server shows many mysql > children while centos shows only one. Here is the pstree result. (Both of > them runs the same version of mysql)Mysql uses threads and doesn't fork off several processes to do the work. Older kernels (or - the older threads version in Linux) show each thread as a new process with its own pid. Recent kernels and pstools just show the pid - so you're not able to see the threads mysql has spawned. You can see those threads with ps, using the "-m" option (show all threads): ps aux -m | grep mysql Regards, Ralph -- Ralph Angenendt......ra at br-online.de | .."Text processing has made it possible Bayerischer Rundfunk...80300 M?nchen | ....to right-justify any idea, even one Programmbereich.Bayern 3, Jugend und | .which cannot be justified on any other Multimedia.........Tl:089.5900.16023 | ..........grounds." -- J. Finnegan, USC -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 189 bytes Desc: not available URL: <http://lists.centos.org/pipermail/centos/attachments/20060720/b56bfa84/attachment-0002.sig>
Thanks Ralph ..I was not aware of this. Thank you very much for clearing my doubt. On Thursday 20 July 2006 04:07 pm, Ralph Angenendt wrote:> Renjith Rajan wrote: > > Hi All, > > > > I have two servers, one is centos 4.3 (new) and other is rh9 (old). > > Both of them run mysql as the primary database server. I installed mysql > > via the rpms available in mysql.com downloads. > > > > Recently when i do "pstree", i noticed that RH9 server shows many mysql > > children while centos shows only one. Here is the pstree result. (Both of > > them runs the same version of mysql) > > Mysql uses threads and doesn't fork off several processes to do the > work. Older kernels (or - the older threads version in Linux) show each > thread as a new process with its own pid. Recent kernels and pstools > just show the pid - so you're not able to see the threads mysql has > spawned. > > You can see those threads with ps, using the "-m" option (show all > threads): > > ps aux -m | grep mysql > > Regards, > > Ralph