Subject: Re: [linux-audio-dev] info point on linux hdr
From: Paul Barton-Davis (pbd_AT_Op.Net)
Date: Sat Apr 22 2000 - 02:24:53 EEST
>As Andreas pointed out, there is no portable/filesystem independent way to
>discover the blocksize used by your FS.
>The thing you are doing in ardour doens't allocate ALL blocks since
>you are using 4096 increments (which is the preferred IO size = intel page
>size),
Oh yeah ?
ardour/track.cc:162:
for (i = statbuf.st_size; i < file_bytes; i += statbuf.st_blksize) {
> and is 4 times as big as the 1024 bytes used by ext2 by default.
Wrong. ext2 picks the fs blocksize mostly according the total size of
the partition, plus the number of inodes to be supported, etc.
pbd[242]>sudo dumpe2fs /dev/sda3 | grep -i size
dumpe2fs 1.18, 11-Nov-1999 for EXT2 FS 0.5b, 95/08/09
Block size: 4096
Fragment size: 4096
Inode size: 128
This fs was created without specifying the blocksize ... satisfied ?
Yes, in theory, there could be a mismatch between the fs blocksize and
st_blksize, but I happen to know that ext2 will "always" use 4K blocks
on a large partition unless its given other parameters that
suggest a better size. Moreover, in the eventual documentation for
ardour, it will state that the fs used for recording *should* be
created with an explicit argument to ensure the blocksize is set to a
known value. OK ?
--p
This archive was generated by hypermail 2b28 : Sat Apr 22 2000 - 02:55:54 EEST