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I am trying to figure out the average write time by datafile using the v$filestat view. The problem is I can't seem to
ever get the WRITETIM or READTIM to display anything but 0.
Yes, I do have TIMED_STATISTICS set to TRUE:)
Has anyone else seen this problem with 8.1.5?
Would anyone have any other suggestions on how to calculate
the average write & read times?
That could also mean that your latency is 0. If you are on unix, then you could use the
iostat -ncxtM 3
view the disk latencies.
Sam
Run the following as sys:
col name for A40
select d.name, a.phyrds, a.phywrts, a.avgiotim
from v$datafile d, v$filestat a
where a.file# = d.file#;
I ran the previous script & AVGIO is still 0.
If I run iostat I get the following:
extended device statistics
r/s w/s Mr/s Mw/s wait actv wsvc_t asvc_t %w %b device
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 c0t0d0
1.0 158.7 0.0 1.2 0.0 1.0 0.0 6.2 0 97 c0t1d0
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 c0t6d0
0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 prime5:vold(pid246)
Shows c0i1d0 is busy writing, yet v$FILESTAT.WRITTIM is still 0. How can that be?
There are currently three open bugs on READTIM being wrong in v$filestat. Bugs 1107600, 1162763, and 1391738.Quote:
Originally posted by salernov
I ran the previous script & AVGIO is still 0.
Which version of Oracle R U using?
8.1.5. Is there a patch?
I don't know. I use 8.1.7.Quote:
Originally posted by salernov
8.1.5. Is there a patch?
If it had not yet been fixed on the 8.1.7 then sure you can expect it to be there on 8.1.5 ;D when the avsc_t goes beyond 20 then you would want to worry too much. Untill then can relax :).
Sam
I got it working. I had to actually set timed_statistics =true
in my init file. The alter session did not work.
If I am using this to calulate my DISK I/O, what is the time scale used by ORACLE in the READTIM & WRITETIM?
I am looking for the # of writes/sec across my mount points.
In the future, you might want to let us know the measures that you took too :DQuote:
Originally posted by salernov
Yes, I do have TIMED_STATISTICS set to TRUE:)
Sam