Wednesday, October 08, 2008


Ptime modifications

Late last year I made a proposal to make some modifications to ptime(1) (the full text of the proposal can be found in the second message here. The proposal includes links to the original RFEs.) There've been some bumps along the way, but the changes are soon going to be putback into Solaris. (Thanks, Rafael!)

When I made these changes, I was mostly just going through the list of open Solaris bugs looking for things to do, it wasn't something that I needed. I've recently found it to be an exceedingly useful tool, though, especially with the -m and -p options. For example, something's just not right with this particular process:

# ptime -mp 3878

real  3:00:47.519957300
user    12:13.948207800
sys        37.210204400
trap    19:40.638837300
tflt        2.942089500
dflt        0.783120500
kflt        0.000000000
lock  5:29:23.879672500
slp   6:00:46.021626100
lat        17.081155000
stop        0.000081200

This is a case of misaligned memory accesses on a SPARC box, which is why all the time is showing up in trap. Here's another process in a bad way:

# ./ptime -mp 2715

real 106:51:30.161266600
user  4:28:49.022048500
sys  19:00:33.201052500
trap        0.047837500
tflt        0.051432200
dflt        0.038230200
kflt        0.000000000
lock 103:08:06.134729400
slp  299:24:41.087893200
lat   1:04:27.602323100
stop        2.913079800

The cause of this aberrant behavior is probably good fodder for a later blog entry.

Comments: Post a Comment

<< Home

This page is powered by Blogger. Isn't yours?