Re: stats on cursor and query execution troubleshooting

Thanks for your repply,  but I still don"t understand why the statistic logs   :

!       0/0 [0/0] filesystem blocks in/out

it told me there is no hard disk access, I'm sure there is,  I heard my HDD,  and see activity using gkrellm (even using my first query ; big select *) ?

2004-10-08 10:40:05 DEBUG:  query: select * from "LINE_Line";
2004-10-08 10:40:53 DEBUG:  QUERY STATISTICS
! system usage stats:
!       48.480196 elapsed 42.010000 user 0.700000 system sec
!       [42.030000 user 0.720000 sys total]
!       0/0 [0/0] filesystem blocks in/out
!       6/23 [294/145] page faults/reclaims, 0 [0] swaps
!       0 [0] signals rcvd, 0/0 [0/0] messages rcvd/sent
!       0/0 [0/0] voluntary/involuntary context switches
! postgres usage stats:
!       Shared blocks:       3902 read,          0 written, buffer hit rate = 11.78%
!       Local  blocks:          0 read,          0 written, buffer hit rate = 0.00%
!       Direct blocks:          0 read,          0 written


looking at the web some logs,  I saw those fields filled (i/o filesystem)
Does my postgresql.conf missing an option or is therer a known bug of my postgresql server  7.2.4 ?



thx
regards

Alban Médici


on 06/10/2004 16:16 Tom Lane said the following:

"Alban Médici (NetCentrex)" <amedici@fr.netcentrex.net> writes: 

I'm looking for the statistic of memory,  CPU,  filesystem access while=20
executing some regular SQL query,  and I want to compare them to
same kind of results while executing a cursor function.   

I think your second query is finding all the disk pages it needs in
kernel disk cache, because they were all read in by the first query.
This has little to do with cursor versus non cursor, and everything
to do with hitting recently-read data again.
		regards, tom lane
 

-- 
Alban Médici
R&D software engineer
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