Re: Question about CPU utilization

As with every rule, there are exceptions. The 4 to 1 ratio applies to many types of systems under various loads. However, the socket connections on HP are expense (they eat a lot of CPU). Move it to the CPU VP and use the new FASTPOLL capability and you will reduce context switching and get better performance, but you won't necessarily see the system utilization drop significantly. On a system with relatively low usage such as you describe, there is substantial overhead with IDS. It is a catch 22 of the architecture and you won't necessarily be able to apply rules like the 4:1 rule. If you have a way to emulate a significant load, I suggest you try to get 300-400 connections hitting the database and see what the ratio is then. The performance guide states that you get optimum performance from a network VP at 350 connections. However, during the benchmark in December we ran 3,000 connections on two VPs on HP. When you get your connections up over 300, you should see ratios closer to what is expected. On Oct 16, 2006, at 3:00 AM, Jörg Rüschenschmidt wrote: > Hi, > > I have question about CPU utilization. My system is a HP UX 11.11 with > IDS 10.00.FC5. I heard once IDS is well configured if you have > usercpu/syscpu relation of >= 4 in onstat -p. > > Today I checked my instance and I found a relation of 2 only. My > conclusion : There is something to tune ! > > I checked onstat -g glo and I found high syscpu in 'soc' class, which > cause the bad total numbers. > > Currently NETTYPE soctcp,1,100,NET is used. I tried to move it to CPU, > because one single thread is used only. This will shift the high > syscpu > to 'cpu' but no improvment in total. > > Furter I tried NETTYPE ipcstr,1,100,NET instead of soctcp. In this > case > 'str' class shows the high syscpu. > > Finally I tried to use FASTPOLL feature, but I could not recognize any > difference. > > It looks like the communication protocol keeps the HP system busy. > > Is there something i missed ? Any ideas ? > > Regards ... > > Joerg Rueschenschmidt > _______________________________________________ > Informix-list mailing list > Informix-list@iiug.org > http://www.iiug.org/mailman/listinfo/informix-list