I want to convert the last of my filesystems to ext3. The only one left is /boot. It is not very big however, only about 10MB itself. Any recommendations on what size journal to put a /boot filesystem of only 10-20MB? Oh, BTW: "tunefs -j -J size=..." is awesome. No more gyrations with dd, chattr, lilo -R, etc. Nice! One note however: even in Stephen's 1.20.WIP.sct-20010216 release, it is an error to use -j without -J ... I seem to recall that -j without -J size is supposed to estimate a journal size and create it. b.
> I want to convert the last of my filesystems to ext3. The only one > left is /boot. It is not very big however, only about 10MB itself. > Any recommendations on what size journal to put a /boot filesystem of > only 10-20MB?It ain't the size, it's how you use it. (Really.) -- Matthew Miller mattdm@mattdm.org <http://www.mattdm.org/> Boston University Linux ------> <http://linux.bu.edu/>
Hi, On Wed, Feb 28, 2001 at 01:25:44PM -0800, Brian J. Murrell wrote:> I want to convert the last of my filesystems to ext3. The only one > left is /boot. It is not very big however, only about 10MB itself. > > Any recommendations on what size journal to put a /boot filesystem of > only 10-20MB?As small as possible! At the moment, that's 1MB for a 1K blocksize filesystem: it should be possible to reduce that, but smaller journals have not been tested.> Oh, BTW: "tunefs -j -J size=..." is awesome. No more gyrations with dd, > chattr, lilo -R, etc. Nice! One note however: even in Stephen's > 1.20.WIP.sct-20010216 release, it is an error to use -j without -J ... > I seem to recall that -j without -J size is supposed to estimate a > journal size and create it. >I'll have a look at that. Cheers, Stephen
Brian Murrell writes:> I want to convert the last of my filesystems to ext3. The only one > left is /boot. It is not very big however, only about 10MB itself. > > Any recommendations on what size journal to put a /boot filesystem of > only 10-20MB?If you make the filesystem with 1k blocks, then you can have a journal of 1MB in size. Basically, you want as small a journal as possible, because /boot is read-mostly, so any journal will just be wasted space. There was some talk about allowing ext3 to have even smaller journals, but I don't think it is a high priority.> Oh, BTW: "tunefs -j -J size=..." is awesome. No more gyrations with dd, > chattr, lilo -R, etc. Nice! One note however: even in Stephen's > 1.20.WIP.sct-20010216 release, it is an error to use -j without -J ... > I seem to recall that -j without -J size is supposed to estimate a > journal size and create it.Yes, I think I made a patch for that one. All that is missing is an "open_flag = EXT2_FLAG_RW;" for the -j option (line 450). I'm hoping Ted will release a new WIP so that I can sync up my changes with him - I sent in a bunch of patches around Christmas (as did Stephen over the last few weeks), but now I'm not sure which ones he saw/used and which ones he missed/discarded. FYI, for the /boot filesystem above "tune2fs -j" would do the correct thing (assuming it was patched) and make the minimum journal size of 1024 filesystem blocks. Cheers, Andreas -- Andreas Dilger \ "If a man ate a pound of pasta and a pound of antipasto, \ would they cancel out, leaving him still hungry?" http://www-mddsp.enel.ucalgary.ca/People/adilger/ -- Dogbert