http://dryice.name/blog Tue, 31 Aug 2010 12:01:11 +0000 http://backend.userland.com/rss092 en This is mostly a note for myself. In 3.2.4, it is said that "for a special file, this i-node contains the major device number, and the minor device number". This is different from what we know for normal files, where the i-node contains file access time, etc. It is not effecient to ... http://dryice.name/blog/minix/different-i-node-for-different-file-type/ I was reading about disk IO this morning. In chapter 3.1.3, it is said that the disk need to be formatted with the number interlaving, so that we'll need less disk circlings to get the data we need. My question is, all these is based on one assumption: that the buffer ... http://dryice.name/blog/minix/disk-io-interleave/ before I started: root@mybox:data# fdisk -s /dev/da0 /dev/da0: 91517 cyl 255 hd 63 sec Part Start Size Type Flags 1: 63 980141652 0xa5 0x80 root@mybox:data# disklabel -A /dev/da0s1 # /dev/da0s1: type: unknown disk: ... http://dryice.name/blog/freebsd/grow-fs/ root@mybox:data# fdisk -s /dev/da0 /dev/da0: 61011 cyl 255 hd 63 sec Part Start Size Type Flags 1: 63 980141652 0xa5 0x80 root@mybox:data# disklabel -A /dev/da0s1 # /dev/da0s1: ... http://dryice.name/blog/freebsd/my-growfs-test/ on the system disk, if I turn the write cache off (sysctl hw.ata.wc, by setting in /boot/loader.conf). the dd command will take 77.78 seconds, well when turning it on (the default), it will take only 10.93 seconds. Share This http://dryice.name/blog/freebsd/write-cache-turns-a-lot/ :(((((( The disk was full when I was downloading something last night. And I didn't notice that this morning. The nearest backup I found was on 3/19. I lost 3 months data of that :((((( Share This http://dryice.name/blog/misc/i-lost-3-months-of-timeclock-data/ mount_cd9660 -s 0 /dev/acd0 /cdrom Share This http://dryice.name/blog/freebsd/mount-cdvcddvd/