Archive for July, 2004

Number 18 of 20: pmap(1) improvements

go to the Solaris 10 top 11-20 list for more pmap(1) For the uninitiated, pmap(1) is a tool that lets you observe the mappings in a process. Here’s some typical output: 311981: /usr/bin/sh 08046000 8K rw— [ stack ] 08050000 80K r-x– /sbin/sh 08074000 4K rwx– /sbin/sh 08075000 16K rwx– [ heap ] C2AB0000 64K [...]





Posted on July 17, 2004 at 10:28 pm by ahl · Permalink · Comments Closed
In: OpenSolaris

Number 13 of 20: Core file improvements

go to the Solaris 10 top 11-20 list for more core files Core files are snapshots of a process’s state. They contain some of the memory segments (e.g. the stack and heap) as well as some of the in-kernel state associated with the process (e.g. the signal masks and register values). When a process gets [...]





Posted on July 15, 2004 at 2:45 pm by ahl · Permalink · 2 Comments
In: OpenSolaris

I/O provider in Solaris Express 7/04

Solaris Express 7/04 is out an includes the I/O provider in DTrace. The I/O provider has just a few probes, but with them you can determine the source of I/O on your system (which processes, or users, or disks, etc.) as well as which files are being accessed, and many other facts that were previously [...]





Posted on July 14, 2004 at 11:31 pm by ahl · Permalink · Comments Closed
In: DTrace

Number 12 of 20: file names in pfiles(1)

go to the Solaris 10 top 11-20 list for more Eric Schrock has tagged in to talk about file names in pfiles(1). This is something we’ve wanted for forever; here’s a teaser: bash-2.05# pfiles 100354 100354: /usr/lib/nfs/mountd Current rlimit: 256 file descriptors 0: S_IFCHR mode:0666 dev:267,0 ino:6815752 uid:0 gid:3 rdev:13,2 O_RDONLY /devices/pseudo/mm@0:null 1: S_IFCHR mode:0666 [...]





Posted on July 13, 2004 at 5:52 pm by ahl · Permalink · Comments Closed
In: OpenSolaris

Number 11 of 20: libumem

go to the Solaris 10 top 11-20 list for more libumem In Solaris 2.4 we replaced the old buddy allocator1 the slab allocator2 invented by Jeff Bonwick. The slab allocator is covered in pretty much every operating systems text book — and that’s because most operating systems are now using it. In Solaris 103, Jonathan [...]





Posted on July 13, 2004 at 5:28 pm by ahl · Permalink · 7 Comments
In: OpenSolaris

The Solaris 10 top 11-20

Solaris 10 has way more features than any release of Solaris that I can remember, and Sun’s been marketing the hell out of them. Here’s my top 10 list roughly in order of how cool I think each is: DTrace- of course… ZFS- the amazing new file system AMD64 Support- Opteron is so obviously great [...]





Posted on July 12, 2004 at 7:00 am by ahl · Permalink · 3 Comments
In: OpenSolaris

Inside nohup -p

I always thought it was cool, but I was surprised by the amount of interest expressed for my recent post on nohup -p. There was even a comment asking how nohup manages the trick of redirecting the output of a running process. I’ll describe in some detail now nohup -p works. First, a little background [...]





Posted on July 9, 2004 at 12:58 pm by ahl · Permalink · One Comment
In: OpenSolaris

Linker alien spotting

After much cajoling, self-described linker alien Rod Evans has joined the fray with his own weblog. As Bryan Cantrill and I will assert again and again, the linker is one of the finest pieces of engineering in all of Solaris, and the Linkers and Libraries Guide is one of the finest pieces of documentation — [...]





Posted on July 7, 2004 at 6:42 pm by ahl · Permalink · Comments Closed
In: OpenSolaris

DTrace as non-root

fintanr’s weblog has a nice entry on how to configure Solaris 10 to give privileges to individual users so they can run DTrace as non-root. By default, users require additional privileges to run DTrace because even providers that don’t expose kernel state explicitly (like the syscall provider) can impact performance on the entire box. The [...]





Posted on July 2, 2004 at 6:48 am by ahl · Permalink · 4 Comments
In: DTrace

old school Solaris and Solaris quality of life

I don’t like to dwell on past Solaris releases, but in Solaris 9 I wrote a cool update for nohup(1). The nohup(1) utility takes a command and its arguments and makes sure that it keeps runnning even if your shell dies or your telnet session drops. Usually the way people use nohup(1) is they login [...]





Posted on July 1, 2004 at 9:45 pm by ahl · Permalink · 10 Comments
In: OpenSolaris