I realize that, when I have 1 threads perform frequent read, and another 3 
threads to perform frequent write. I will get the following error log 
*sometimes*

2010-05-07 17:16:10 MYT LOG checkpoints are occurring too frequently (22 
seconds apart) 
2010-05-07 17:16:10 MYT HINT Consider increasing the configuration parameter 
"checkpoint_segments". 
2010-05-07 17:31:37 MYT LOG checkpoints are occurring too frequently (29 
seconds apart) 
2010-05-07 17:31:37 MYT HINT Consider increasing the configuration parameter 
"checkpoint_segments". 

My observation is, even the above logging happen, "write" operation is success 
when I exam the content of database.

What happen is that, the read operation fail. 

read thread is spawned after 3 write threads, and read thread will only be 
considered as "success", only when its read result is same as what is being 
written by the 3 threads. The read threads will perform retry for every 200ms, 
lasted for 4 seconds.

I was thinking, what is the consequent of increasing "checkpoint_segments", 
say, from 3 to 6. Any bad thing might happen?

Thanks and Regards
Yan Cheng CHEOK


      


-- 
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general

Reply via email to