Re: NUMAIOVPS setting
"Art S. Kagel" <kagel@bloomberg.net> schrieb: >NO, io/wup can indeed fall below 1.0 if you are configured correctly, and I >DO indeed mean you shoule monitor io/wup. If you are showing io/wup 1.0 or >above for all aio VPs then you will improve performance (EVEN if all of your >chunks are RAW and you are using KAIO for chunk accesses) by increasing the >number of AIO VPs until at least one of these show io/wup <1.0 (ie: 0.9 or >0.8). Has anyone running Informix 7.3 under Linux ever seen an io/wup value < 1.0? Art's observations seem to be platform dependent; my own experience with IDS 7.31UD5 under SuSE 7.2 (Kernel 2.4.18) is that no matter how many AIO VPs I configured, they never went below 1.0, although most stay at exactly 1.0 What about Informix 9.x? Regards, Richard -- +-------------------------------+-------------------------------+ | Dr. med Richard Spitz | Tel : +49-89-7095-6110 | | Klinik f'r Anaesthesiologie | FAX : +49-89-7095-6420 | | Klinikum der Univ. M'nchen | Page: +49-89-7095-789-2116 | | 81366 M'nchen, Germany | | +-------------------------------+-------------------------------+
On Tue, 01 Jun 2004 04:13:53 -0400, Richard Spitz wrote: OK, a bit of clarity and apology. IFF you are running on a single CPU system with a single CPU VP then you cannot physically get an io/wup value < 1.0. However, if you add a second CPU VP on a P4 or higher (due to the virtual CPU feature of those processors) or on a machine with multiple CPUs, then you will absolutely be able to see io/wup <1.0 if aio is tuned well. Running on 20-32 processor boxes gets me jaded sometimes. I forget we're not all running massive iron. Sorry. Art S. Kagel > "Art S. Kagel" <kagel@bloomberg.net> schrieb: > >>NO, io/wup can indeed fall below 1.0 if you are configured correctly, and I >>DO indeed mean you shoule monitor io/wup. If you are showing io/wup 1.0 or >>above for all aio VPs then you will improve performance (EVEN if all of your >>chunks are RAW and you are using KAIO for chunk accesses) by increasing the >>number of AIO VPs until at least one of these show io/wup <1.0 (ie: 0.9 or >>0.8). > > Has anyone running Informix 7.3 under Linux ever seen an io/wup value < 1.0? > Art's observations seem to be platform dependent; my own experience with IDS > 7.31UD5 under SuSE 7.2 (Kernel 2.4.18) is that no matter how many AIO VPs I > configured, they never went below 1.0, although most stay at exactly 1.0 > > What about Informix 9.x? > > Regards, Richard