Thanks Mike. > Is it unresponsive only when dtrace is running or > normally?
It becomes unresponsive after starting Dtrace. > With recent releases of Solaris, I've found systems to be > quite responsive > with a load average that is many times higher than > the number of CPU's > (as seen by mpstat - 128 for the typical dual > processor T5140/T5240). The system is a T5440. 256G RAM. > It seems highly unlikely that the problem is related > to being short on > CPU (again, only at about 12% CPU utilization). vmstat reports more than 95%CPU free. core utilization is between 2-3% > > If it is unresponsive or sluggish before you start > dtrace, I would > guess that one of the following is the case: No. It gets sluggish after Dtrace is started. > - The machine is short on RAM and is paging. Use > vmstat to diagnose. > Look at the "b" column (blocked on I/O) and paging > related columns > such as sr (scan rate). You would see things as being > extremely > sluggish (e.g. when executing a command) because the > disk reads needed > to load the commands and related libraries are > getting queue behind > the IO requests for paging. > there's plenty of RAM ~240G > - The network is having troubles. Look for a duplex > mismatch or > non-zero values in: > > kstat -p e1000g | nawk '$NF != 0 && $0 ~ > /(err|drop|fail)/' > - There is some other I/O problem. Does iostat -En > show hard errors > on any disk? Does "iostat -xzn 1" show svc_time + > wsvc_time over > 20ms? How many I/Os are queued and active? > > > Your question is performance - but you jumped to the > conclusion that > dtrace would tell you the answer. It may, but there > are likely other > tools that will be helpful with a lot less effort and > less system > impact. perf-discuss may be a better list to ask for > more help. we were checking application performance when we enaged this script to check where the hot spots were; we had to Ctrl-c dtrace because of it behavior. Even now on a idle server (same system) here is what is what I see, although not that unresponsive now ( vey little load to start with) Before dtrace: Total: 162 processes, 2058 lwps, load averages: 0.79, 2.87, 2.26 Total: 162 processes, 2058 lwps, load averages: 1.03, 2.89, 2.27 After Dtrace Total: 161 processes, 2057 lwps, load averages: 20.61, 6.88, 3.61 Total: 161 processes, 2057 lwps, load averages: 38.40, 10.76, 4.93 Total: 161 processes, 2057 lwps, load averages: 35.38, 10.59, 4.91 This time I was able to get some o/p from the script otherwise with load I have not seen script o/p. Now you can imagine the state of the system if the initail load was 10-15. Please let mw know if you need more details. -- This message posted from opensolaris.org _______________________________________________ dtrace-discuss mailing list dtrace-discuss@opensolaris.org
