[Zope] ZEO Problem Clients Waiting

[Dieter Maurer]

Gerhard Schmidt wrote at 2006-8-7 15:54 +0200:
> ...
>2006-08-07T14:29:19 INFO ZEO.StorageServer (97002/10.152.64.23:52518)
>Transaction
>+blocked waiting for storage. Clients waiting: 1.
> ...
>2006-08-07T14:29:50 INFO ZEO.StorageServer (97002/10.152.64.17:54463) Blocked transaction restarted.  Clients waiting: 1
>2006-08-07T14:29:50 INFO ZEO.StorageServer (97002/10.152.64.23:52518) Blocked transaction restarted.
>
>This one was a very quick one only 30 seconds. I have Blocked Transaktion
>that ware waiting for more than 2 minutes.

This means that you have very long transactions -- transactions that
take very long to commit.

ZEO cannot commit two transactions for the same storage at the same time.
Therefore, it sets a storage look when a transaction commit begins for
the storage.

If another transaction tries to commit to the same storage, the transaction
is blocked until the first transaction commit completes.
That's your "Transaction blocked waiting for storage...."

When the commit is completed, then a waiting transaction is restarted.
That's your "Blocked transaction restarted".

You should try to understand where the huge transactions come from.
Very often, they are caused by poor persistency design (either far
too huge objects or an immense number of tine objects or just some stupidity
(e.g. writing objects unnecessary).



-- 
Dieter