BOSTON - The conference started today, at a bright 9am. My first full day course was "Advanced Solaris System Administration Topics, taught by Peter Baer Galvin.

It was a useful and enlightening class, mostly for the historical perspective and for the discussion on Solaris 9/10 features.

Some nuggets:

• Crash Dumps - Mike Shapiro, a Sun kernel guy, suggests that crash dumps not be written where they can be lost (temp space). He also suggests the use of dumpadm which will let you direct dumps to use raw disk.
• Autoclient - Autoclient is dead.
• Swap - Galvin explains that swap usage is allocated in a round-robin fashion, in 1MB increments. If you choose to have >1 swap partitions, put them on separate disks or even controllers. But, if you're using swap, you might have bigger problems... Always mirror your swap space. Swapping is 10^4 slower than RAM.
• # swap -l vs. swap -s - # swap -l reports on true swap, swap -s actually includes physical memory, thus reports on virtual memory.
• Shutting Down - halt and reboot skip the "K" files, which can be bad for database servers, since things aren't shutdown cleanly.
• Recovery - Ever damage your /etc/system so badly that you can't boot? Use boot -a to specify the path to a backup copy of the file or even point it to /dev/null to get your host back on its feet.
• Exiting Faster - pgrep and pkill make your scripts shut the system down faster by accessing the /proc filesystem directly rather than the kludgy grepping of ps output.
• "short read" errors - Too many files in /.
• Privileges - Solaris 10 will be adding substantial new features, notably expanded privileges to allow finer grained control than setuid can provide.
• Inodes - When creating a filesystem, tune the number of inodes created to fit your application. Mail and news use a lot, databases comparatively few.
• Intent Logging - File creation rates increase from 5/second to 200/second using intent logging. This is the default in Sol10, optional in Sol9, and should be feared and avoided in Sol8.
• UFS - Sun claims that UFS performance is on par with vxfs in Solaris 9.
• VXFS - Due to its extent-based approach, vxfs actually suffers from fragmentation and needs to be de-fragged. The utility to do this must be manually enabled.
• New commands - Lots of new "p" commands for working with processes: pcred, pflags, pmap, psig, pstop, ptree, pfiles.
• ZFS - "The next great thing". Sun is working on the zetabyte file system, which is "infinitely" expansible, and uses an allocation model, similar to malloc() for memory. Let's hope that it is better behaved... ZFS breaks any backwards compatibility with UFS.
• Tuning and benchmarking - Change only one thing at a time. Reboot. Measure. Repeat. More spindles is always better. Each of the many tools, vmstat, iostat, mpstat, sar, lockstat, netstat each provide a small piece of the puzzle when tuning or troubleshooting. Learn what they are each telling you.
• CPU's - Sun possesses "M-values" calculations for all CPU's which can help you get a solid idea about relative performance. Oracle considers the Sparc4 arhictecture as 2-CPU's. Beware of licensing charges.
• http://blogs.sun.com/bmc

Excellent class, nearly 400 slides of information.