Lazy Reading for 2011/04/03

Getting into the swing of this link collection thing…

Double buffering in Hammer usually useful

Enabling the vfs.hammer.double_buffer=1 sysctl will greatly improve Hammer performance when you’ve exceeded your memory cache (at a possible slight penalty when you have not) and also speed things up when using live deduplication.

Update: Venkatesh Srinivas says:

“double_buffer makes sense when: 1) you want all CRCs to be checked on reads. 2) you’re running live dedup and care about dedup performance rather than say read-heavy performance; 3) you have swapcache but are often running into the  vnode limit in what you can cache.”

So, not always useful.

binutils, Hammer updates

Sascha Wildner has updated the default version of binutils in DragonFly from 2.17 to 2.21.  You’ll want to do a full buildworld on your next upgrade, if you’re running DragonFly 2.9.

Also, Matthew Dillon has made version 6 the default version of Hammer in DragonFly 2.9.   Version 6 has improved handling of directory names in some circumstances.  Just don’t ask me which, cause I lost track.  It’s been a hard day!