[Zope] ZServer and MySQL: wierd behavior

AM list_subscriber@neurobs.com
Tue, 18 Mar 2003 17:23:16 -0800


I found a strange problem on my install.
I run Zope 2.6.1 (Zserver) behind Apache 2.0 on a dual processor RedHat 
7.3 box and have a MySQL 4.0.1 db (uses InnoDB tables) that keeps my 
user data.

I have custom user folder based heavily on the mysqluserfolder product 
that authenticates users off the db.  

I also have a sign-up process that is a multiform page and uses 
transactions to insert data into the db (separate from the user folder, 
the userfolder interfaces for the same are just dummy functions).

What I saw was that if for some reason mysql deadlocked over multiple 
transaction writing to the same table (ie multiple users signing up at 
the same time on the site) and dropped some of the transactions, Zope 
just waited around forever and eventually became unresponsive. Apache 
then returns a 502 - Server overload/busy.

Once I dropped the transaction commands (begin/commit) everything worked 
smoothly.

What I would like to know is that if MySQL recovered gracefully why was 
Zope waiting around for the dropped transactions to return something.?

TIA
AM

-- 
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 Aseem Mohanty							   
 Neurobehavioral Systems Inc, 828 San Pablo Ave, Albany, CA 94706 
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 "I saw `cout' being shifted "Hello world" times to the left and  
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