DB2 Tip: Finding Basic OS Information on DB2 Servers

Usually, there’s an admin (well, lots of them for different clients) I ask when I have basic questions about system configurations, but like all DBAs, sometimes I need to figure it out myself. Enter db2pd -osinfo.

The -osinfo option on db2pd can give you some of the basic information on OS configuration without having to know or google OS level commands to find it. Recently, I was interested in the number of CPUs on several servers, and I used db2pd -osinfo.

Authorization

The authorities needed for db2pd vary by version. With 8.2 and before, you had to be the instance owner. DB2 9.1 allowed those with SYSADM to run db2pd. DB2 9.1 Fixpack 6 and later allow those with SYSMON, SYSMAINT, SYSCTRL, or SYSADM to run db2pd.

OSINFO

db2pd -osinfo gives a bunch of information. This is what it looks like:

$ db2pd -osinfo

Operating System Information:

OSName:   Linux      
NodeName: 403906-Perf-db1.redacted.com 
Version:  2                    
Release:  6          
Machine:  x86_64     

CPU Information:
TotalCPU    OnlineCPU   ConfigCPU   Speed(MHz)  HMTDegree  Cores/Socket
12          12          12          2394        2           6          

Physical Memory and Swap (Megabytes):
TotalMem    FreeMem     AvailMem    TotalSwap   FreeSwap   
48289       1041        n/a         2048        2044        

Virtual Memory (Megabytes):
Total       Reserved    Available   Free       
50337       n/a         n/a         3083        

Message Queue Information:
MsgSeg      MsgMax      MsgMap      MsgMni      MsgTql      MsgMnb      MsgSsz               
n/a         65536       65536       48128       65536       65536       16          

Shared Memory Information:
ShmMax               ShmMin               ShmIds      ShmSeg      
68719476736          1                    12032       12032       

Semaphore Information:
SemMap      SemMni      SemMns      SemMnu      SemMsl      SemOpm      SemUme      SemUsz      SemVmx      SemAem      
256000      12032       256000      256000      250         32          n/a         20          32767       32767       

CPU Load Information:
Short     Medium    Long      
1.160000  1.080000  0.960000  

CPU Usage Information (percent):
Total     Usr       Sys       Wait      Idle      
9.666667  n/a        n/a        n/a        90.333333 

If you go through it line by line, there’s some good information here. The CPU information is up front, and includes not just the number of CPUs and cores, but also the MHz, which could be especially useful to know in a virtual environment. The Physical Memory (it is 48 GB in my example) is good to be able to get this way, along with the other lines of memory details. There’s a line for CPU Load, and finally, usage information – which I’m quite used to getting through vmstat, but is also here. Think how many commands I would have had to run at the OS level to get that information at the OS level. This also lets someone like me, who uses a windows server about once every 3 years, have a standard way to get at the most basic OS information that I might need to know.