Re: Shared Memory Tuning

Andrew J. Saville wrote: > > Does anybody out there know why Online 7.1 reserves 99% of swap space on > our HP9000/K400 running HPUX 10.01. We have 640 mb of ram and over 600 > mb of swap. The shmax parameter is set to it's highest setting possible. > I don't have my notes with me, but it is something like 0x4000000. > > This swap reservation causes other processes not to be able to start. > Buffers in informix are set to 60,000. This was 100,000 but had to be > reduces to start other processes. This seems to be the only informix > parameter that affects this swap reservation. Well, I don't think this has anything to do specifically with informix. I believe that on HP in general, the OS must reserve enough swap space for a process, in its entirety, to be swapped out if need be. So the biggest part of online is shared memory which all the oninits need to attach to and the largest part of shared memory generally tends to be the buffer pool. Which is why reducing it to 60,000 helped out. So, if I remember my HP classes correctly, the OS is reserving enough swap space for the shared memory segments that are being created, even if they never swap out, it still reserves the space. Jacques -- ******************************************************************** * Jacques P. Renaut "I'd dazzle you with brilliance * * Informix Advanced Support if I only had the knack..." * * email: jrenaut@informix.com #include <disclamier.h> * ********************************************************************