Do Something Every Day

I’ve been using FLAC to backup my CDs for some time, but due to the ubiquity of MP3, I frequently found myself transcoding a large number of these files for various devices.

I found a good number of scripts[1] for doing the conversion, and it seems to be  a bike shed everyone wants to chime in on.  What I found didn’t really handle modern multi-core processors, so I made some quick tweaks and thought I’d post my results.  There are two scripts:

mp3xcode:

#!/bin/bash

mkdir mp3
parallel mp3xcode_sub — *.flac

mp3xcode_sub:

#!/bin/bash

[ -r "$1" ] || { echo can not read file \”$1\” >&1 ; exit 1 ; } ;

FLAC=$1
MP3=”mp3/${FLAC%.flac}.mp3″

eval `metaflac –export-tags-to=- “$FLAC” | sed ‘s/=\(.*\)/=”\1″/’`

flac -dc “$FLAC” | lame –replaygain-accurate -v -V 2 –tt “$TITLE” \
–tn “$TRACKNUMBER” \
–tg “$GENRE” \
–ty “$DATE” \
–ta “$ARTIST” \
–tl “$ALBUM” \
–add-id3v2 \
- “$MP3″

This script seems to be a good way to do it. I’ve only tested this on linux.

On FreeBSD, there may be some tweaks required to not depend on bash.  Also, you’ll need to install the GNU parallel program (sysutils/parallel).

Having followed the http://wiki.freebsd.org/ZFSTuningGuide, when configuring ZFS, I was aware of the delicate nature of the kernel settings for ZFS on i386.  I recently upgraded my server to 4GB ECC from 2GB non-ECC and thought I’d like to take advantage of the extra ram, so I thought I’d play around with these options.

My current kernel config could not be simpler, ZFS-GENERIC:

include    GENERIC
ident    ZFS-GENERIC
options    KVA_PAGES=512

For this configuration I successfully used in /boot/loader.conf:

#Working options for ZFS-GENERIC 2GB RAM, KVA_PAGES=512
vm.kmem_size=”1536M”
vm.kmem_size_max=”1536M”
vfs.zfs.arc_max=”786M”

I thought it would be as simple as:

#Trial options for ZFS-GENERIC 4GB RAM, KVA_PAGES=512
vm.kmem_size=”2G”
vm.kmem_size_max=”2G”
vfs.zfs.arc_max=”1792M”

But, but to my chagrin, my system responded on boot up with a:

panic: kmem_suballoc: bad status return of 3

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