Impact of transaction log backups in synchronous DB Mirroring syst

Hello,
We have a site on SQL Server 2005 SP2 EE. They are using synchronous
database mirroring. Both the principal and mirror are on a fast LAN. When
they perform transaction log backups on the principal database, our
application that accesses the principal database freezes for 1 or 2 seconds.
The transaction log backups are being written to the same disk where the
database resides. They have tried reducing the frequency of the transaciton
log backups to every 10 minutes, and that reduced the length of the app
freeze, but did not eliminate it. Has anyone heard of a problem running
transaction log backups when the database is mirrored?
Thanks,
Heather
I would be more concerned as to the placement of the log backups. Why would
you write them to the same disk that hold the data files? This is definitely
a candidate for a performance hit not to mention a problem if the disk
itself crashes. You loose both the data and logs and are probably in line to
update the resume. If you saturate the I/O the db can appear to freeze.
Andrew J. Kelly SQL MVP
Solid Quality Mentors
"HeatherK" <HeatherK@.community.nospam> wrote in message
news:E6A9E23D-916B-4CEE-8C3F-8801CD3394EB@.microsoft.com...
> Hello,
> We have a site on SQL Server 2005 SP2 EE. They are using synchronous
> database mirroring. Both the principal and mirror are on a fast LAN. When
> they perform transaction log backups on the principal database, our
> application that accesses the principal database freezes for 1 or 2
> seconds.
> The transaction log backups are being written to the same disk where the
> database resides. They have tried reducing the frequency of the
> transaciton
> log backups to every 10 minutes, and that reduced the length of the app
> freeze, but did not eliminate it. Has anyone heard of a problem running
> transaction log backups when the database is mirrored?
> Thanks,
> Heather
|||Hi Andrew,
Thanks for your post.
Yes, we realize that the placement of the backup files is not optimal. They
are using RAID5 on the drive, so they should be protected from a disk crash.
We realize RAID 5 is not optimal for performance, but that is what they have.
We have not seen a problem with transaction log backups at our other sites
that are not using Database Mirroring. That is why we were wondering if
there were any known issues with taking transaction log backups when you are
using synchronous Database Mirroring.
We will gather more performance metrics to determine if this is strictly
related to I/O or if there is a connection with Database Mirroring.
Thanks,
Heather
"Andrew J. Kelly" wrote:

> I would be more concerned as to the placement of the log backups. Why would
> you write them to the same disk that hold the data files? This is definitely
> a candidate for a performance hit not to mention a problem if the disk
> itself crashes. You loose both the data and logs and are probably in line to
> update the resume. If you saturate the I/O the db can appear to freeze.
> --
> Andrew J. Kelly SQL MVP
> Solid Quality Mentors
>
> "HeatherK" <HeatherK@.community.nospam> wrote in message
> news:E6A9E23D-916B-4CEE-8C3F-8801CD3394EB@.microsoft.com...
>
|||Well mirroring does add overhead and potentially even a little more I/O on
the drive with the logs so I am sure it adds to the whole mess. Doing a log
backup also forces a checkpoint which is I/O intensive as well. What do the
perfmon counters and virtual file statsw say for that drive and the log
files? And by the way you should never count on the fact that it is Raid 5
to avert a crash. They would be better off copying the files to a network
share.
Andrew J. Kelly SQL MVP
Solid Quality Mentors
"HeatherK" <HeatherK@.community.nospam> wrote in message
news:C0FB6FB3-9661-4BAA-84D2-17AC2B7C1A6F@.microsoft.com...[vbcol=seagreen]
> Hi Andrew,
> Thanks for your post.
> Yes, we realize that the placement of the backup files is not optimal.
> They
> are using RAID5 on the drive, so they should be protected from a disk
> crash.
> We realize RAID 5 is not optimal for performance, but that is what they
> have.
> We have not seen a problem with transaction log backups at our other sites
> that are not using Database Mirroring. That is why we were wondering if
> there were any known issues with taking transaction log backups when you
> are
> using synchronous Database Mirroring.
> We will gather more performance metrics to determine if this is strictly
> related to I/O or if there is a connection with Database Mirroring.
> Thanks,
> Heather
> "Andrew J. Kelly" wrote:

Impact of transaction log backups in synchronous DB Mirroring syst

Hello,
We have a site on SQL Server 2005 SP2 EE. They are using synchronous
database mirroring. Both the principal and mirror are on a fast LAN. When
they perform transaction log backups on the principal database, our
application that accesses the principal database freezes for 1 or 2 seconds.
The transaction log backups are being written to the same disk where the
database resides. They have tried reducing the frequency of the transaciton
log backups to every 10 minutes, and that reduced the length of the app
freeze, but did not eliminate it. Has anyone heard of a problem running
transaction log backups when the database is mirrored?
Thanks,
HeatherI would be more concerned as to the placement of the log backups. Why would
you write them to the same disk that hold the data files? This is definitely
a candidate for a performance hit not to mention a problem if the disk
itself crashes. You loose both the data and logs and are probably in line to
update the resume:). If you saturate the I/O the db can appear to freeze.
--
Andrew J. Kelly SQL MVP
Solid Quality Mentors
"HeatherK" <HeatherK@.community.nospam> wrote in message
news:E6A9E23D-916B-4CEE-8C3F-8801CD3394EB@.microsoft.com...
> Hello,
> We have a site on SQL Server 2005 SP2 EE. They are using synchronous
> database mirroring. Both the principal and mirror are on a fast LAN. When
> they perform transaction log backups on the principal database, our
> application that accesses the principal database freezes for 1 or 2
> seconds.
> The transaction log backups are being written to the same disk where the
> database resides. They have tried reducing the frequency of the
> transaciton
> log backups to every 10 minutes, and that reduced the length of the app
> freeze, but did not eliminate it. Has anyone heard of a problem running
> transaction log backups when the database is mirrored?
> Thanks,
> Heather|||Hi Andrew,
Thanks for your post.
Yes, we realize that the placement of the backup files is not optimal. They
are using RAID5 on the drive, so they should be protected from a disk crash.
We realize RAID 5 is not optimal for performance, but that is what they have.
We have not seen a problem with transaction log backups at our other sites
that are not using Database Mirroring. That is why we were wondering if
there were any known issues with taking transaction log backups when you are
using synchronous Database Mirroring.
We will gather more performance metrics to determine if this is strictly
related to I/O or if there is a connection with Database Mirroring.
Thanks,
Heather
"Andrew J. Kelly" wrote:
> I would be more concerned as to the placement of the log backups. Why would
> you write them to the same disk that hold the data files? This is definitely
> a candidate for a performance hit not to mention a problem if the disk
> itself crashes. You loose both the data and logs and are probably in line to
> update the resume:). If you saturate the I/O the db can appear to freeze.
> --
> Andrew J. Kelly SQL MVP
> Solid Quality Mentors
>
> "HeatherK" <HeatherK@.community.nospam> wrote in message
> news:E6A9E23D-916B-4CEE-8C3F-8801CD3394EB@.microsoft.com...
> > Hello,
> >
> > We have a site on SQL Server 2005 SP2 EE. They are using synchronous
> > database mirroring. Both the principal and mirror are on a fast LAN. When
> > they perform transaction log backups on the principal database, our
> > application that accesses the principal database freezes for 1 or 2
> > seconds.
> >
> > The transaction log backups are being written to the same disk where the
> > database resides. They have tried reducing the frequency of the
> > transaciton
> > log backups to every 10 minutes, and that reduced the length of the app
> > freeze, but did not eliminate it. Has anyone heard of a problem running
> > transaction log backups when the database is mirrored?
> >
> > Thanks,
> > Heather
>|||Well mirroring does add overhead and potentially even a little more I/O on
the drive with the logs so I am sure it adds to the whole mess. Doing a log
backup also forces a checkpoint which is I/O intensive as well. What do the
perfmon counters and virtual file statsw say for that drive and the log
files? And by the way you should never count on the fact that it is Raid 5
to avert a crash. They would be better off copying the files to a network
share.
--
Andrew J. Kelly SQL MVP
Solid Quality Mentors
"HeatherK" <HeatherK@.community.nospam> wrote in message
news:C0FB6FB3-9661-4BAA-84D2-17AC2B7C1A6F@.microsoft.com...
> Hi Andrew,
> Thanks for your post.
> Yes, we realize that the placement of the backup files is not optimal.
> They
> are using RAID5 on the drive, so they should be protected from a disk
> crash.
> We realize RAID 5 is not optimal for performance, but that is what they
> have.
> We have not seen a problem with transaction log backups at our other sites
> that are not using Database Mirroring. That is why we were wondering if
> there were any known issues with taking transaction log backups when you
> are
> using synchronous Database Mirroring.
> We will gather more performance metrics to determine if this is strictly
> related to I/O or if there is a connection with Database Mirroring.
> Thanks,
> Heather
> "Andrew J. Kelly" wrote:
>> I would be more concerned as to the placement of the log backups. Why
>> would
>> you write them to the same disk that hold the data files? This is
>> definitely
>> a candidate for a performance hit not to mention a problem if the disk
>> itself crashes. You loose both the data and logs and are probably in line
>> to
>> update the resume:). If you saturate the I/O the db can appear to
>> freeze.
>> --
>> Andrew J. Kelly SQL MVP
>> Solid Quality Mentors
>>
>> "HeatherK" <HeatherK@.community.nospam> wrote in message
>> news:E6A9E23D-916B-4CEE-8C3F-8801CD3394EB@.microsoft.com...
>> > Hello,
>> >
>> > We have a site on SQL Server 2005 SP2 EE. They are using synchronous
>> > database mirroring. Both the principal and mirror are on a fast LAN.
>> > When
>> > they perform transaction log backups on the principal database, our
>> > application that accesses the principal database freezes for 1 or 2
>> > seconds.
>> >
>> > The transaction log backups are being written to the same disk where
>> > the
>> > database resides. They have tried reducing the frequency of the
>> > transaciton
>> > log backups to every 10 minutes, and that reduced the length of the app
>> > freeze, but did not eliminate it. Has anyone heard of a problem
>> > running
>> > transaction log backups when the database is mirrored?
>> >
>> > Thanks,
>> > Heather
>>sql

Impact of transaction log backups in synchronous DB Mirroring syst

Hello,
We have a site on SQL Server 2005 SP2 EE. They are using synchronous
database mirroring. Both the principal and mirror are on a fast LAN. When
they perform transaction log backups on the principal database, our
application that accesses the principal database freezes for 1 or 2 seconds.
The transaction log backups are being written to the same disk where the
database resides. They have tried reducing the frequency of the transaciton
log backups to every 10 minutes, and that reduced the length of the app
freeze, but did not eliminate it. Has anyone heard of a problem running
transaction log backups when the database is mirrored?
Thanks,
HeatherI would be more concerned as to the placement of the log backups. Why would
you write them to the same disk that hold the data files? This is definitely
a candidate for a performance hit not to mention a problem if the disk
itself crashes. You loose both the data and logs and are probably in line to
update the resume. If you saturate the I/O the db can appear to freeze.
Andrew J. Kelly SQL MVP
Solid Quality Mentors
"HeatherK" <HeatherK@.community.nospam> wrote in message
news:E6A9E23D-916B-4CEE-8C3F-8801CD3394EB@.microsoft.com...
> Hello,
> We have a site on SQL Server 2005 SP2 EE. They are using synchronous
> database mirroring. Both the principal and mirror are on a fast LAN. When
> they perform transaction log backups on the principal database, our
> application that accesses the principal database freezes for 1 or 2
> seconds.
> The transaction log backups are being written to the same disk where the
> database resides. They have tried reducing the frequency of the
> transaciton
> log backups to every 10 minutes, and that reduced the length of the app
> freeze, but did not eliminate it. Has anyone heard of a problem running
> transaction log backups when the database is mirrored?
> Thanks,
> Heather

IIS Virtual Directory Manager and IIS 6: Template requests not being actioned.

Hi,
I have XML Data Islands on my page that are correctly requesting data
from the Virtual Directory. I can see the requests in the IIS log.
However the virtual directory doesn't seem to be returning anything -
no error message no nothing. When I run the same query from IE6
directly it runs fine.
I have run a trace on the database and nothing is being requested.
How can I debug this - is there an error log somewhere that I could
look at? What am I missing?
Info: SQL Server 2000 SP4 is on a separate database. I am using
Integrated Windows Authentication and delegation.
Cheers,
JamesSorry, this was specific to our setup... ignore.
JimLad wrote:

> Hi,
> I have XML Data Islands on my page that are correctly requesting data
> from the Virtual Directory. I can see the requests in the IIS log.
> However the virtual directory doesn't seem to be returning anything -
> no error message no nothing. When I run the same query from IE6
> directly it runs fine.
> I have run a trace on the database and nothing is being requested.
> How can I debug this - is there an error log somewhere that I could
> look at? What am I missing?
> Info: SQL Server 2000 SP4 is on a separate database. I am using
> Integrated Windows Authentication and delegation.
> Cheers,
> James

iis log report

hi i want to create a report using iis log
how can i do it

i can do it by transferring log to a sql table
but isn't it a way to directly use log file in reportThe best way would be to directly let the log populate in a ODBC database where you can directly report from.

HTH, Jens K. Suessmeyer.

http://www.sqlserver2005.de

|||But i m using W3C Extended log file,
i need to create report using this file as this format provide much more detail then ODBC option.

should i use custom data extension.

IIS 4 Hangs to SQL 2000

Hello everyone,

I've done some searching, asking of friends, and searching every log file and event file I can think of. So now I'm coming here.

Recently I moved some of our databases from an NT4 box running SQL 7 to an Advanced 2000 box running SQL 2000. The web server is still on an NT4 box. It seems that about three times a day or so ASP type files will hang on the webserver. This server hosts different sites and all ASP type files will stop even if some of them hit the old SQL7 server.

Right now I moved the web server back to looking at the SQL 7 machine and things are going fine.

Can anyone offer me a direction to start looking? Why is it working fine to the old stuff but not the new stuff? Is there an issue with NT4 with its IIS trying to talk to an Advanced 2000 with its SQL2000?

Thank you in advance for any help.Are you getting any logs in the event logs when this happens? Are you using ADO to connect to both boxes (7.0 and 2000)? What version is your MDAC or connection dll's at?|||All three MDACs are at 2.6. I say three because of the old SQL7, new SQL2000, and the webserver.

It is using DSN connection on some items. There is one item that I'm not sure of because I didn't code it. Some time ago one of my managers (not with us any more) wrote our Content Managment Assistant (CMA). It is a Java com object. He created it so it gets the server, user, and password information from a registry key.

Just a bit more information, ever since I changed the webserver to go back to the old SQL7 machine there have been no problems. I will gladly get you any more information that might help, but I may need a little more info on finding it, for example, which DLLs in question are you wanting me to check?

Thank you again.