6.0 Shared Memory Usage
Apologies if this have been covered before but:
On NCR (4.3) using Online 6.00.UE1G6, we started Online, ran one of
our maintentance jobs (which takes about 8-10 hours), and now shared
memory usage is now up to the 290 MB mark, and climbing.
Other than an occasional dbaccess, no other process is using Informix.
Assuming that we aren't doing anything _stupid_, is this normal
behavior for 6.0+? I understand from the book Informix-OnLine
Performance Tuning that:
"Once these segments have been allocated, they cannot be de-allocated
except by bringing down the OnLine system. Note, however, that
shared memory pages are treated like any other memory. They can be
paged out if real memory is needed for any other purpose."
Does this mean I need to configure a googaplex of swap space? Is
this reasonable behavior (for Informix)?
We have experienced the same behavior during a benchmark on
HP-UX (w 7.1) where shared-memory usage approached 1GB.
(Luckily we had 2 GB in the box, and 3 GB of swap, so no problem, 8:) )
Comments?
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|James Bennett | Phone: 916.891.5281 |
|Bi-Tech Software, Inc | Fax : 916.891.5011 |
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