deadlocks not resolved by SQL Server

I am under the impression that SQL Server would automatically detect a
deadlock and roll back a participating transaction. However, I have had a
few cases where automatic resolution did not occur. Instead, I had to go in
and manually kill the transaction that is causing a deadlock.
Is there anyway to avoid this? I don't want to have to manually kill a
transaction to unwind a deadlock if that's at all possible.
Thanks in advanceHi
It sounds like you have prolonged blocking rather than a deadlock, in which
case your query should timeout. Make sure that your application has
overridden the default timeouts and requested to wait indefinitely.
You should also investigate if you application has long running transactions
that have not been correctly committed/rolled back or if poor indexing is
affecting performance.
John
"C.W." wrote:
> I am under the impression that SQL Server would automatically detect a
> deadlock and roll back a participating transaction. However, I have had a
> few cases where automatic resolution did not occur. Instead, I had to go in
> and manually kill the transaction that is causing a deadlock.
> Is there anyway to avoid this? I don't want to have to manually kill a
> transaction to unwind a deadlock if that's at all possible.
> Thanks in advance
>
>

deadlocks not resolved by SQL Server

I am under the impression that SQL Server would automatically detect a
deadlock and roll back a participating transaction. However, I have had a
few cases where automatic resolution did not occur. Instead, I had to go in
and manually kill the transaction that is causing a deadlock.
Is there anyway to avoid this? I don't want to have to manually kill a
transaction to unwind a deadlock if that's at all possible.
Thanks in advanceHi
It sounds like you have prolonged blocking rather than a deadlock, in which
case your query should timeout. Make sure that your application has
overridden the default timeouts and requested to wait indefinitely.
You should also investigate if you application has long running transactions
that have not been correctly committed/rolled back or if poor indexing is
affecting performance.
John
"C.W." wrote:

> I am under the impression that SQL Server would automatically detect a
> deadlock and roll back a participating transaction. However, I have had a
> few cases where automatic resolution did not occur. Instead, I had to go i
n
> and manually kill the transaction that is causing a deadlock.
> Is there anyway to avoid this? I don't want to have to manually kill a
> transaction to unwind a deadlock if that's at all possible.
> Thanks in advance
>
>

Deadlock info

Hello,
Does the deadlock information automatically gets written to
the Sql errorlog or do we have enable traces 3604&1204,if we
enable does these flags degrade any performance or does it uses resorces
on the sql server machine.(Anything noticeable)
Thanks in advance.
Hi,
You have to turn on the trace flags so that deadlock victim info is dumped
into the errorlog with more details.DBCC TRACEON will turn the flag on for
that connection and DBCC TRACEOFF will turn it off.I have only used them for
a short period of time, so the performance degradation , if any, was hardly
noticeable.
Dinesh
SQL Server MVP
--
SQL Server FAQ at
http://www.tkdinesh.com
"sc" <anonymous@.discussions.microsoft.com> wrote in message
news:C8E78861-6B34-4AEE-97CC-D6ADC30F7DD3@.microsoft.com...
> Hello,
> Does the deadlock information automatically gets written to
> the Sql errorlog or do we have enable traces 3604&1204,if we
> enable does these flags degrade any performance or does it uses resorces
> on the sql server machine.(Anything noticeable)
> Thanks in advance.
>
|||Hi,
No, By default the trace flags are not enabled.
Enabling this trace flag for all users will definitely degrade performance .
But obviously during problem situation you have enable
it for analysis purpose.
Thanks
Hari
MCDBA
"sc" <anonymous@.discussions.microsoft.com> wrote in message
news:C8E78861-6B34-4AEE-97CC-D6ADC30F7DD3@.microsoft.com...
> Hello,
> Does the deadlock information automatically gets written to
> the Sql errorlog or do we have enable traces 3604&1204,if we
> enable does these flags degrade any performance or does it uses resorces
> on the sql server machine.(Anything noticeable)
> Thanks in advance.
>

Deadlock info

Hello,
Does the deadlock information automatically gets written to
the Sql errorlog or do we have enable traces 3604&1204,if we
enable does these flags degrade any performance or does it uses resorces
on the sql server machine.(Anything noticeable)
Thanks in advance.Hi,
You have to turn on the trace flags so that deadlock victim info is dumped
into the errorlog with more details.DBCC TRACEON will turn the flag on for
that connection and DBCC TRACEOFF will turn it off.I have only used them for
a short period of time, so the performance degradation , if any, was hardly
noticeable.
Dinesh
SQL Server MVP
--
--
SQL Server FAQ at
http://www.tkdinesh.com
"sc" <anonymous@.discussions.microsoft.com> wrote in message
news:C8E78861-6B34-4AEE-97CC-D6ADC30F7DD3@.microsoft.com...
> Hello,
> Does the deadlock information automatically gets written to
> the Sql errorlog or do we have enable traces 3604&1204,if we
> enable does these flags degrade any performance or does it uses resorces
> on the sql server machine.(Anything noticeable)
> Thanks in advance.
>|||Hi,
No, By default the trace flags are not enabled.
Enabling this trace flag for all users will definitely degrade performance .
But obviously during problem situation you have enable
it for analysis purpose.
Thanks
Hari
MCDBA
"sc" <anonymous@.discussions.microsoft.com> wrote in message
news:C8E78861-6B34-4AEE-97CC-D6ADC30F7DD3@.microsoft.com...
> Hello,
> Does the deadlock information automatically gets written to
> the Sql errorlog or do we have enable traces 3604&1204,if we
> enable does these flags degrade any performance or does it uses resorces
> on the sql server machine.(Anything noticeable)
> Thanks in advance.
>

dbo option only

Hi,
Can you change the mode to dbo option only if there are other users connected? Will they automatically get booted out?
MeeraHowdy

If you try & change to db_use only, an error will come up saying people are using the database & the task will fail.

Cheers

SG