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SQL CPU Utilization goes to 0

Patrick Moore
Guest
 
Posts: n/a
#1: Jul 20 '05
We have a SQL 7.0 Standard Server running on a Windows 2000 Server
machine with 2 800mhz Pentium III with 2GB memory. Our front end is
Access 97 and 2000 with most ADO connections for the scripts but some
DAO for forms and reports. We recently "released" a new version of
the "database" that caused a catastrophic event to start happening
with our SQL server.

Using PerfMon we monitored the CPU utilization on the server and
noticed that the CPU load would drop to 0 for approx 5-10 seconds and
then jump back up to our average 60-70% utilization. During this
drop, there is NO disk activity no new connections being made, etc.
We then took the process a step further and loaded a "stress" program
that put about 30% load on the server to start with. Then we
monitored each processes load. SQL Server process would drop to 0%
while the stress process continued at 30%.

The problem is that the SQL does absolutely NOTHING for 5-10 seconds.
You cannot connect, any querys that are running stop, their is no disk
activity (logs, data drives), and you cannot even get sp_who2 to run
from Query Analyser. We thought maybe blocking (we have built an
"app" that monitors this), but we don't see any blocking before it
locks and nothing after it locks.

Out of despiration we "rolled back" to our previous version to get
people working again. After business hours, we have tried to
duplicate the problem on machines (2 or 3 at a time) but cannot get it
to duplicate the problem.

The only experience we had previous to this was using DNS to resolve
the server name which caused a problem EXTREMELY familar to this
problem. However, we have double checked every machine we have, and
none of them are using DNS to resolve.

Any idea's would be most appreciated.

Patrick Moore

Jake Jessup
Guest
 
Posts: n/a
#2: Jul 20 '05

re: SQL CPU Utilization goes to 0


To www.sysinternals.com and download two programs. One is called Filemon,
the other is Regmon.

I suspect Filemon will help you more.

This will show you if there is any file or registry activity at all and if
not, will likely reveal what file was running and causes the CPU to drop.

I would also suggest taking an image of the production server, putting it on
similar hardware and reinstalling your upgrade. Heck, you might even want to
image it and do it on the same machine (after getting a proper backup AND
the image file).

Regmon is similar to filemon but may provide clues to what's going on as
well.

I hope this helps.

"Patrick Moore" <patrick@wyrmhole.org> wrote in message
news:4e024fd1.0406221655.7032c65f@posting.google.c om...[color=blue]
> We have a SQL 7.0 Standard Server running on a Windows 2000 Server
> machine with 2 800mhz Pentium III with 2GB memory. Our front end is
> Access 97 and 2000 with most ADO connections for the scripts but some
> DAO for forms and reports. We recently "released" a new version of
> the "database" that caused a catastrophic event to start happening
> with our SQL server.
>
> Using PerfMon we monitored the CPU utilization on the server and
> noticed that the CPU load would drop to 0 for approx 5-10 seconds and
> then jump back up to our average 60-70% utilization. During this
> drop, there is NO disk activity no new connections being made, etc.
> We then took the process a step further and loaded a "stress" program
> that put about 30% load on the server to start with. Then we
> monitored each processes load. SQL Server process would drop to 0%
> while the stress process continued at 30%.
>
> The problem is that the SQL does absolutely NOTHING for 5-10 seconds.
> You cannot connect, any querys that are running stop, their is no disk
> activity (logs, data drives), and you cannot even get sp_who2 to run
> from Query Analyser. We thought maybe blocking (we have built an
> "app" that monitors this), but we don't see any blocking before it
> locks and nothing after it locks.
>
> Out of despiration we "rolled back" to our previous version to get
> people working again. After business hours, we have tried to
> duplicate the problem on machines (2 or 3 at a time) but cannot get it
> to duplicate the problem.
>
> The only experience we had previous to this was using DNS to resolve
> the server name which caused a problem EXTREMELY familar to this
> problem. However, we have double checked every machine we have, and
> none of them are using DNS to resolve.
>
> Any idea's would be most appreciated.
>
> Patrick Moore[/color]


Vincento Harris
Guest
 
Posts: n/a
#3: Jul 20 '05

re: SQL CPU Utilization goes to 0


"Jake Jessup" <watcherdude@hotmail.com> wrote in message news:<F26Cc.76408$EK5.32404@newssvr29.news.prodigy .com>...[color=blue]
> To www.sysinternals.com and download two programs. One is called Filemon,
> the other is Regmon.
>
> I suspect Filemon will help you more.
>
> This will show you if there is any file or registry activity at all and if
> not, will likely reveal what file was running and causes the CPU to drop.
>
> I would also suggest taking an image of the production server, putting it on
> similar hardware and reinstalling your upgrade. Heck, you might even want to
> image it and do it on the same machine (after getting a proper backup AND
> the image file).
>
> Regmon is similar to filemon but may provide clues to what's going on as
> well.
>
> I hope this helps.
>
> "Patrick Moore" <patrick@wyrmhole.org> wrote in message
> news:4e024fd1.0406221655.7032c65f@posting.google.c om...[color=green]
> > We have a SQL 7.0 Standard Server running on a Windows 2000 Server
> > machine with 2 800mhz Pentium III with 2GB memory. Our front end is
> > Access 97 and 2000 with most ADO connections for the scripts but some
> > DAO for forms and reports. We recently "released" a new version of
> > the "database" that caused a catastrophic event to start happening
> > with our SQL server.
> >
> > Using PerfMon we monitored the CPU utilization on the server and
> > noticed that the CPU load would drop to 0 for approx 5-10 seconds and
> > then jump back up to our average 60-70% utilization. During this
> > drop, there is NO disk activity no new connections being made, etc.
> > We then took the process a step further and loaded a "stress" program
> > that put about 30% load on the server to start with. Then we
> > monitored each processes load. SQL Server process would drop to 0%
> > while the stress process continued at 30%.
> >
> > The problem is that the SQL does absolutely NOTHING for 5-10 seconds.
> > You cannot connect, any querys that are running stop, their is no disk
> > activity (logs, data drives), and you cannot even get sp_who2 to run
> > from Query Analyser. We thought maybe blocking (we have built an
> > "app" that monitors this), but we don't see any blocking before it
> > locks and nothing after it locks.
> >
> > Out of despiration we "rolled back" to our previous version to get
> > people working again. After business hours, we have tried to
> > duplicate the problem on machines (2 or 3 at a time) but cannot get it
> > to duplicate the problem.
> >
> > The only experience we had previous to this was using DNS to resolve
> > the server name which caused a problem EXTREMELY familar to this
> > problem. However, we have double checked every machine we have, and
> > none of them are using DNS to resolve.
> >
> > Any idea's would be most appreciated.
> >
> > Patrick Moore[/color][/color]


Without knowing too much about your system
I will highly recommend you run a trace/profiler
A poorly indexed and highly accessed table
has been known to bring things to a halt.
After you do that feed the index tuning
wizard with the trace file for a start
May be that will put out the heat

Vincento
Closed Thread


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