Solaris kernel parm sd_max_throttle

[John]

With Symmetrix, what are some of you seeing sd_max_throttle set to . A
shop has it set to 20, which I believe is an EMC recommendation. Is
this ok? It basically limits number of outstanding requests (cause of
command tag queueing). I'm concerned that is is throttling back DB2
too much....Thx, Flick

[PM \(pm3iinc-nospam\) CGO]

I know close to nothing about solaris and emc systems but most modern scsi
adapters can hold
more than 20 for sure.

The number of requests you can handle also depends on the size of the io's
you do. (max Scatter Gather list/ the io size)
If i remember correctly, an adapter can serve lots of small io's of a few
larger ones.
On windows, you can set driver parameters like MaximumSGList and
NumberOfRequests.
You must watch them both. (the number and size of io's)
"John" <jo******@hotmail.com> a écrit dans le message de
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With Symmetrix, what are some of you seeing sd_max_throttle set to . A
shop has it set to 20, which I believe is an EMC recommendation. Is
this ok? It basically limits number of outstanding requests (cause of
command tag queueing). I'm concerned that is is throttling back DB2
too much....Thx, Flick