If both your policies (schedules on that) and storage units are set to use 32 as MPX, you are surely having problems with memory allocation. 32 is a very high value (the maximum NBU supports) and is not used in normal situations. To get the best MPX level, we normally made lots of tests with different configurations (either MPX and different values for Buffers size and number) and practically never get to 32.
Also, a so high MPX number can bring some other issues, like constant 100% network device usage, in the majority of the cases cause low throughput to the clients in environment, make NBU Media Server unavailable during backup, cause high restore time (specially if 'Reduce Fragment Size' is not properly configured) and so on.
A customer had a similar problem and I fixed it proving him that 32 was a unnecessary number. Today, after studding the environment, the highest MPX for some policies he has is 15 and all backups run faster as well as backup window decrease considerably.
You should decrease these values to something more normal. After many many studies, I've never set MPX to more than 16 and even this 16 is for some very specific backups, like Exchange Mailboxes (till 6.5.2, now we don't need it any more) or Oracle Archives or SQL Transactions. The other ones, like Unix or Windows file system backups works better up to 6 or 7.
Of course, to know the best value for your environment, or for some specific policies, you need to make exhaustive tests.
Message Edited by Raphael Carvalho on 01-27-2009 05:14 PM
