monSysWaits event 150 - what a meaning of "Number of times tasks waited..."

[former_member427820]

In case of monSysWaits event 150 - how can I interpret the waits "Number of times tasks waited...".

Is this always the number  of blocked processes?

And why the counter changes only after block has released, but not during the block.

Actually when block started the system already waits, but the monSysWaits doesn't indicate this.

[former_member89972]

WaitEventId 150 is Waiting for a lock.

So :

select count(*) from monProcess where WaitEventId = 150

go

will give you the number of blocked processes at that point in time.

SAP/Sybase document mentions only these as historical tables

monErrorLog

monDeadLock

monSysStatement

monSysSQLText

monSysPlanText

My guess is that  monSysWaits table is also a historical (aka pipe) table.

So the data gets in SYS mon tables only AFTER the completion as a history

i.e not while current execution is still in progress.

HTH

Avinash

[former_member89972]

I may stand corrected !

monSysWaits is different than the other historical MDA tables mentioned above --- in the sense that repeated query on a single connection includes rows shown earlier.  On the historical tables above repeated queries on the same connection will exclude the rows shown earlier.

HTH

Avinash