Re: Slow file access on Compact Flash
On 2008-10-20, Uwe Dippel [EMAIL PROTECTED] wrote: [I read all postings in the archive AFAIK] Just started with CF on embedded hardware advertised to run OpenBSD; ARInfoTek. It does run OpenBSD very well! Now I want the embedded system to run off CF; the board has a CF socket to be wd0. 4.2 runs out of the box, but with very slow access of files. The CF is reasonably fast, though, with ~6MB at 'dd'. But once it has to access files for r/w, it gets very slow. I found some postings that 4.3 would be better, but the install of 4.3 here mainly -stalled- and took a good hour, from a local ftp-site. locate.updatedb is incredibly fast, while some file extraction takes ages. It looks like a large, single, file copies very fast, similar to 'dd'. But opening a file for r/w seems to take ages. Something like tar -C /tmp -xzphf etc43.tgz takes a minute, easily. And etc43.tgz is only 1.2MB. Copying of this file is quick: $ date cp etc43.tgz demo date Mon Oct 20 11:29:15 SGT 2008 Mon Oct 20 11:29:16 SGT 2008 How are you doing the install? If it's from a running system rather than the installer, you might want to mount -uoasync / (and /usr if it's on a separate filesystem) to avoid rewriting the directories quite so many times. Note that erasing/rewriting CF is very slow; when even one bit moves from 0 to 1 the whole flash block must be erased and copied to another one.
Re: Slow file access on Compact Flash [SOLVED]
Uwe Dippel wrote: 4.2 runs out of the box, but with very slow access of files. The CF is reasonably fast, though, with ~6MB at 'dd'. But once it has to access files for r/w, it gets very slow. Any hint welcome, I got a really great hint. Let me start with the results: tar -C /tmp -xzphf etc43.tgz takes exactly 3 min 16 sec With softdep on, it takes exactly 2 seconds. Thanks so much! Now CF is as fast as hard disk. (I use a 133x Kingston) Uwe
Re: Slow file access on Compact Flash
Uwe Dippel [EMAIL PROTECTED] writes: [I read all postings in the archive AFAIK] Just started with CF on embedded hardware advertised to run OpenBSD; ARInfoTek. It does run OpenBSD very well! Now I want the embedded system to run off CF; the board has a CF socket to be wd0. 4.2 runs out of the box, but with very slow access of files. The CF is reasonably fast, though, with ~6MB at 'dd'. But once it has to access files for r/w, it gets very slow. I found some postings that 4.3 would be better, but the install of 4.3 here mainly -stalled- and took a good hour, from a local ftp-site. locate.updatedb is incredibly fast, while some file extraction takes ages. It looks like a large, single, file copies very fast, similar to 'dd'. But opening a file for r/w seems to take ages. Something like tar -C /tmp -xzphf etc43.tgz takes a minute, easily. And etc43.tgz is only 1.2MB. Copying of this file is quick: $ date cp etc43.tgz demo date Mon Oct 20 11:29:15 SGT 2008 Mon Oct 20 11:29:16 SGT 2008 Any hint welcome, try soft update : http://openbsd.org/faq/faq14.html#SoftUpdates -- Guillaume Pinot http://www.irccyn.ec-nantes.fr/~pinot/ ``Computers are good at following instructions, but not at reading your mind.'' -- Donald E. Knuth, the TeXbook () ASCII ribbon campaign -- Against HTML e-mail /\ http://www.asciiribbon.org -- Against proprietary attachments
