Hi Denis, It's too early to determine if you need a memory upgrade. First let's analyze the situation... At first look your CPU seems to be overcommited because the idle column is about 11%. But if you sum the columns user and system it's about 23%. This is your real CPU utilization, so it's too low. You can utilize until 70-80% of your CPU. Your wait column it's really worry! It means that you have an I/O bottleneck. How's your iostat? Althought the scaned pages column to be too high the relationship with freeing is not more than 4:1, even in your case that are much pi/po. In other words your real memory it's not overcommited. The avm column shows that you are only using about 532MB of your real memory. Much probably you are using most part of the other 500MB of real memory to cache the filesystems. If the DB, LOG e stgpool volumes are on filesystems and you are using the defaults of VMM, so you can change these parameters through the vmtune. The parameters that change the cache of filesystems are maxperm (-P) and minperm (-p) to 10 and 5% respectively. The vmtune it's located on /usr/samples/kernel. If you don't find this directory so you need to install the bos.adt.samples.kernel. I think that's the name of fileset. Anyway tell me if you have some problem. Two things you should know about vmtune: the first is that you can change online but to feel the diference it's better to reboot the system to flush the filesystem cache. The second is every time that you reboot your operating system you must re-execute the vmtune with your parameters. So put an entry in your inittab to execute the vmtune command every IPL.
Regards, Anderson > Hello- > I am having a memory problem. > I am runnning AIX 4.3.2 on a H50. TSM is the only application > running on the server. When I run vmstat I get the following... > > kthr memory page faults cpu > ----- ----------- ------------------------ ------------ ----------- > r b avm fre re pi po fr sr cy in sy cs us sy id wa > 0 0 136233 202 0 3 2 99 210 0 52 240 66 17 30 16 37 > 1 3 136234 342 0 38 11 3727 4204 0 1322 6136 4665 12 11 3 74 > 2 3 136236 160 0 44 12 3728 5326 0 1324 5844 4644 10 11 2 76 > 1 3 136237 295 0 17 19 4113 5725 0 1305 7174 5091 13 10 3 74 > 0 3 136237 629 0 19 9 4240 7442 0 1316 7200 5082 14 13 5 68 > > Does this look normal to anyone? From my limited understanding of vmstat > it looks like: > CPU utilization is maxed out > I have blocked processes (the b column) > The scan rate (sr) column is very high. > The server has 1Gig of memory. I'm really not sure how to tell how much is > allocated to > the OS and how much is allocated to TSM. Does anyone have any ideas or > pointers is > tuning memory for AIX? Do I need a memory upgrade? > I started checking this because my server response is horrible. > Thanks. > Denis >
