Hi, I think we're mis-reading the conversation a little. I agree, with your explanation, it's the same as my explanation and the same as a the user guide. There is no confusion here - it works for me as you describe. The issue is is that with 3 stripes, the size of each stripe is (n)/3. For a 90GB file, this is still 30GB per stripe. Given restarting glusterfsd breaks the "mirrors", this will still require at least 30GB to be copied on self-heal. (which isn't workable) The way in which this "would" be usable if if the striping process broke the file down into "many" files, typically down to the chunk size .. which would make the self-heal process reasonably quick. Unfortunately creating a config file with 5,000 stripes also seems a little unworkable. Regards, Gareth ----- Original Message ----- From: "Csibra Gergo" <gergo@xxxxxxxxx> To: gluster-devel@xxxxxxxxxx Sent: Friday, December 28, 2007 10:21:17 AM (GMT) Europe/London Subject: Re: Choice of Translator question Friday, December 28, 2007, 1:05:09 AM, Kevan Benson wrote: > Gareth Bult wrote: >> This could be the problem. >> >> When I do this on a 1G file, I have 1 file in each stripe partition of size ~ 1G. >> >> I don't get (n) files where n=1G/chunk size ... (!) >> >> If I did, I could see how it would work .. but I don't .. >> >> Are you saying I "definitely should" see files broken down into multiple sub files, or were you assuming this is how it worked? > That sounds like the striping isn't working Well, the answer is yes for Gareth and no for Kevan. The stripe translator works :) See this: gergolaptop:/mnt/gluster1# ls -la összesen 26021 drwxr-xr-x 3 root root 1024 2007-12-28 11:03 . drwxr-xr-x 17 root root 4096 2007-12-28 10:58 .. -rw-r--r-- 1 root root 104660992 2007-12-28 11:03 glusterimg1 drwx------ 2 root root 12288 2007-12-03 22:09 lost+found As you see the glusterimg1 file looks like 1 100MB size, but... gergolaptop:/mnt/gluster1# du -h glusterimg1 26M glusterimg1 It occupies only 26MB (striped to four pieces) gergolaptop:/mnt/gluster1# df . Fájlrendszer 1K-blokk Foglalt Szabad Fo.% Csatl. pont /mnt/glusterimg1 99150 31668 62362 34% /mnt/gluster1 And you see here too, the disk is only 100MB size, and only 31668 are occupied (Foglalt means occupied in hungarian, Szabad is free). All of the striped files are sparse files. Sparse files are occupy disk space only they use. So if you create a file, seeks to 100MB, and write there only 1 byte, the file will looks like a 100MB file, but will only occupy 1 byte (not 1 byte, 1024,2048,4096 it depends the block and chunk size of the filesystem). see more here: http://en.wikipedia.org/wiki/Sparse_file -- Best regards, Csibra Gergo mailto:gergo@xxxxxxxxx _______________________________________________ Gluster-devel mailing list Gluster-devel@xxxxxxxxxx http://lists.nongnu.org/mailman/listinfo/gluster-devel
