[HACKERS] why we need both the collector & buffer process

[William.Jiang]

hi,all hackers of postgres
    when postmaster start as a service . another two processes(collector & buffer ) start their work at the same time.
   I have read the code and I am wondering why we need two processes to do the work. I think one process can work as well. Are there something special you considered when you developed this feature?
  Best wishes!
  William
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Re: [HACKERS] why we need both the collector & buffer process

[William.Jiang]

Sorry to say that I cannot see which process is used to do checkpoints. I just see two main functions. 
 pgstat_recvbuffer(): this function is to receive the information from the postgres .this function is the main body of buffer process 
pgstat_min():this function is to do the job of  getting information from the buffer process and writing them to the file . and this is the main body of collector process. 
Any function else to do the checkpoint job? 
Best Wishes! 
William 
   Bruce Momjian <[EMAIL PROTECTED]> wrote:
=?gb2312?q?William.Jiang?= wrote:> > hi,all hackers of postgres> > when postmaster start as a service . another two> processes(collector & buffer ) start their work at the same> time.> > I have read the code and I am wondering why we need two> processes to do the work. I think one process can work as> well. Are there something special you considered when you> developed this feature?One collects statistics for the pg_stat tables, and the other doescheckpoints. They are different functions.--Bruce Momjian | http://candle.pha.pa.us[EMAIL PROTECTED] | (610) 359-1001+ If your life is a hard drive, | 13 Roberts Road+ Christ can be your backup. | Newtown Square, Pennsylvania 19073Do You Yahoo!?
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