Re: [gentoo-user] Re: can't create file but disk isn't full
Willie Wong writes: When the filesystem fills up, services can start failing left and right because they cannot write logs, cannot write temp files, etc. At this point human intervention is necessary: root has to log in and clear out the disk. But if the $ROOT filesystem is completely full, one may not even be able to log in and/or that one cannot do any sort of maintenance that is needed. So you have some sort of circularity. (In which case you have to reboot, perhaps using another medium...) The way out is to reserve some breathing room for root so that when everybody else is having problems he can still get in and fix the problem. The 5% is historical from days when disks are much smaller. If you have a sensible partition scheme you only really need to reserve the blocks on the $ROOT filesystem. If the partition in question (IIRC) is only for /home, then you can just turn off the reserved blocks all together. Isn't another purpose of those 5% the reduction of fragmentation that occurs more when there is few free space left? Although I also reduce ift on very large partitions. But I never set it to exactly zero. Wonko
Re: [gentoo-user] Re: can't create file but disk isn't full
On Thu, May 13, 2010 at 12:25:08AM +0200, Alex Schuster wrote: The 5% is historical from days when disks are much smaller. If you have a sensible partition scheme you only really need to reserve the blocks on the $ROOT filesystem. If the partition in question (IIRC) is only for /home, then you can just turn off the reserved blocks all together. Isn't another purpose of those 5% the reduction of fragmentation that occurs more when there is few free space left? Although I also reduce ift on very large partitions. But I never set it to exactly zero. Perhaps? I don't know. My ext3 partitions with 0% are all for large files (videos and music) that are more or less static, so I can't say anything about fragmentation on them. My other partitions are all reiser, so can't say anything about fragmentation on them either :) W -- Willie W. Wong ww...@math.princeton.edu Data aequatione quotcunque fluentes quantitae involvente fluxiones invenire et vice versa ~~~ I. Newton
[gentoo-user] Re: can't create file but disk isn't full
On 05/13/2010 01:56 AM, Willie Wong wrote: On Thu, May 13, 2010 at 12:25:08AM +0200, Alex Schuster wrote: The 5% is historical from days when disks are much smaller. If you have a sensible partition scheme you only really need to reserve the blocks on the $ROOT filesystem. If the partition in question (IIRC) is only for /home, then you can just turn off the reserved blocks all together. Isn't another purpose of those 5% the reduction of fragmentation that occurs more when there is few free space left? Although I also reduce ift on very large partitions. But I never set it to exactly zero. Perhaps? I don't know. My ext3 partitions with 0% are all for large files (videos and music) that are more or less static, so I can't say anything about fragmentation on them. My other partitions are all reiser, so can't say anything about fragmentation on them either :) The tune2fs man page mentions that fragmentation is also a reason: -m reserved-blocks-percentage Set the percentage of the filesystem which may only be allocated by privileged processes. Reserving some number of filesystem blocks for use by privileged processes is done to avoid filesystem fragmentation, and to allow system daemons, such as syslogd(8), to continue to function correctly after non- privileged processes are prevented from writing to the filesystem. Normally, the default percentage of reserved blocks is 5%.
Re: [gentoo-user] Re: can't create file but disk isn't full
On Sun, May 09, 2010 at 07:39:01PM -0300, Crístian Viana wrote: what exactly is this reserved block count? is it about the number of inodes? does that mean that, by default, regular users can only use 95% of the inodes? and why did I use all these inodes? I don't think I have that many small files on this partition... When the filesystem fills up, services can start failing left and right because they cannot write logs, cannot write temp files, etc. At this point human intervention is necessary: root has to log in and clear out the disk. But if the $ROOT filesystem is completely full, one may not even be able to log in and/or that one cannot do any sort of maintenance that is needed. So you have some sort of circularity. (In which case you have to reboot, perhaps using another medium...) The way out is to reserve some breathing room for root so that when everybody else is having problems he can still get in and fix the problem. The 5% is historical from days when disks are much smaller. If you have a sensible partition scheme you only really need to reserve the blocks on the $ROOT filesystem. If the partition in question (IIRC) is only for /home, then you can just turn off the reserved blocks all together. Cheers, W -- Willie W. Wong ww...@math.princeton.edu Data aequatione quotcunque fluentes quantitae involvente fluxiones invenire et vice versa ~~~ I. Newton
Re: [gentoo-user] Re: can't create file but disk isn't full
thanks! I'll set it to 0% then. On Mon, May 10, 2010 at 12:48 PM, Willie Wong ww...@math.princeton.eduwrote: On Sun, May 09, 2010 at 07:39:01PM -0300, Crístian Viana wrote: what exactly is this reserved block count? is it about the number of inodes? does that mean that, by default, regular users can only use 95% of the inodes? and why did I use all these inodes? I don't think I have that many small files on this partition... When the filesystem fills up, services can start failing left and right because they cannot write logs, cannot write temp files, etc. At this point human intervention is necessary: root has to log in and clear out the disk. But if the $ROOT filesystem is completely full, one may not even be able to log in and/or that one cannot do any sort of maintenance that is needed. So you have some sort of circularity. (In which case you have to reboot, perhaps using another medium...) The way out is to reserve some breathing room for root so that when everybody else is having problems he can still get in and fix the problem. The 5% is historical from days when disks are much smaller. If you have a sensible partition scheme you only really need to reserve the blocks on the $ROOT filesystem. If the partition in question (IIRC) is only for /home, then you can just turn off the reserved blocks all together. Cheers, W -- Willie W. Wong ww...@math.princeton.edu Data aequatione quotcunque fluentes quantitae involvente fluxiones invenire et vice versa ~~~ I. Newton
Re: [gentoo-user] Re: can't create file but disk isn't full
root can create new files! I created a big file with the remaining 17 GB logged in with root. I'll run this tune2fs later, before shutting down the machine. what exactly is this reserved block count? is it about the number of inodes? does that mean that, by default, regular users can only use 95% of the inodes? and why did I use all these inodes? I don't think I have that many small files on this partition... On Sat, May 8, 2010 at 10:48 PM, Nikos Chantziaras rea...@arcor.de wrote: On 05/09/2010 01:46 AM, Crístian Viana wrote: it doesn't seem so :-( FilesystemInodes IUsed IFree IUse% Mounted on /dev/sda620856832 108698 207481341% /home I didn't know that the filesystem could run out of inodes before the disk space itself! thanks for the information :-) Long shot, but check if root can write files. If yes, it probably means your reserved block count is a bit high (default is 5% I believe). The reserved block count is a mechanism that disallows further writes to the filesystem if it gets too full, and only root can keep writing. If that's your problem, the reserved block count can be changed with the tune2fs tool. To set it to, say 2%, you would run: tune2fs -m 2 /dev/sda6 I don't know if it's safe to do this while the filesystem is mounted. To play it safe, go to single user mode, umount /home, and only then run the above command.
[gentoo-user] Re: can't create file but disk isn't full
On 05/08/2010 09:21 PM, Crístian Viana wrote: hi everyone, something weird is happening on my system. I can't create new files, it says No space left on device, but the disk has several gigabytes of free space! The filesystem probably ran out of inodes. df -i /home will show inode usage. This can happen when you have many small files; they eat inodes but not storage space.
Re: [gentoo-user] Re: can't create file but disk isn't full
it doesn't seem so :-( FilesystemInodes IUsed IFree IUse% Mounted on /dev/sda620856832 108698 207481341% /home I didn't know that the filesystem could run out of inodes before the disk space itself! thanks for the information :-) On Sat, May 8, 2010 at 4:07 PM, Nikos Chantziaras rea...@arcor.de wrote: On 05/08/2010 09:21 PM, Crístian Viana wrote: hi everyone, something weird is happening on my system. I can't create new files, it says No space left on device, but the disk has several gigabytes of free space! The filesystem probably ran out of inodes. df -i /home will show inode usage. This can happen when you have many small files; they eat inodes but not storage space.
Re: [gentoo-user] Re: can't create file but disk isn't full
You probably have files opened that have since been deleted. du doesn't report them as the names are no longer in the directory and df doesn't report them as they are pending deletion once the last handle to them is closed. It's a nasty thing to find. Run this: lsof | grep deleted You should find a ton of junk temp files (they will go away when you log out). Look for big numbers in column 8 On Sunday 09 May 2010 00:46:28 Crístian Viana wrote: it doesn't seem so :-( FilesystemInodes IUsed IFree IUse% Mounted on /dev/sda620856832 108698 207481341% /home I didn't know that the filesystem could run out of inodes before the disk space itself! thanks for the information :-) On Sat, May 8, 2010 at 4:07 PM, Nikos Chantziaras rea...@arcor.de wrote: On 05/08/2010 09:21 PM, Crístian Viana wrote: hi everyone, something weird is happening on my system. I can't create new files, it says No space left on device, but the disk has several gigabytes of free space! The filesystem probably ran out of inodes. df -i /home will show inode usage. This can happen when you have many small files; they eat inodes but not storage space. -- alan dot mckinnon at gmail dot com
Re: [gentoo-user] Re: can't create file but disk isn't full
I shutdown this computer everyday, those temp files shouldn't be alive for months. I ran lsof | grep deleted and it returned 132 lines, the biggest number being 2032226 (2 MB?), belonging to the Chromium browser process. even if every line had that value (which is not), that would sum up 264 MB, but the difference of reported/real free space is way bigger than that. changing the filesystem back to ext3 can solve this problem? it was ext3 before I've changed it to ext4 some months ago. On Sat, May 8, 2010 at 8:00 PM, Alan McKinnon alan.mckin...@gmail.comwrote: You probably have files opened that have since been deleted. du doesn't report them as the names are no longer in the directory and df doesn't report them as they are pending deletion once the last handle to them is closed. It's a nasty thing to find. Run this: lsof | grep deleted You should find a ton of junk temp files (they will go away when you log out). Look for big numbers in column 8 On Sunday 09 May 2010 00:46:28 Crístian Viana wrote: it doesn't seem so :-( FilesystemInodes IUsed IFree IUse% Mounted on /dev/sda620856832 108698 207481341% /home I didn't know that the filesystem could run out of inodes before the disk space itself! thanks for the information :-) On Sat, May 8, 2010 at 4:07 PM, Nikos Chantziaras rea...@arcor.de wrote: On 05/08/2010 09:21 PM, Crístian Viana wrote: hi everyone, something weird is happening on my system. I can't create new files, it says No space left on device, but the disk has several gigabytes of free space! The filesystem probably ran out of inodes. df -i /home will show inode usage. This can happen when you have many small files; they eat inodes but not storage space. -- alan dot mckinnon at gmail dot com
Re: [gentoo-user] Re: can't create file but disk isn't full
On Sunday 09 May 2010 01:39:54 Crístian Viana wrote: I shutdown this computer everyday, those temp files shouldn't be alive for months. I ran lsof | grep deleted and it returned 132 lines, the biggest number being 2032226 (2 MB?), belonging to the Chromium browser process. even if every line had that value (which is not), that would sum up 264 MB, but the difference of reported/real free space is way bigger than that. changing the filesystem back to ext3 can solve this problem? it was ext3 before I've changed it to ext4 some months ago. I'm fresh out of ideas on this one. As I understand it, downgrading from ext4 to ext3 normally doesn't work out. There are features in ext4 that make it very attractive and most folk enable them, but they are incompatible with ext3. Or so I have read. I would boot into a rescue system and run an fsck on that volume if you have not already done so. On Sat, May 8, 2010 at 8:00 PM, Alan McKinnon alan.mckin...@gmail.comwrote: You probably have files opened that have since been deleted. du doesn't report them as the names are no longer in the directory and df doesn't report them as they are pending deletion once the last handle to them is closed. It's a nasty thing to find. Run this: lsof | grep deleted You should find a ton of junk temp files (they will go away when you log out). Look for big numbers in column 8 On Sunday 09 May 2010 00:46:28 Crístian Viana wrote: it doesn't seem so :-( FilesystemInodes IUsed IFree IUse% Mounted on /dev/sda620856832 108698 207481341% /home I didn't know that the filesystem could run out of inodes before the disk space itself! thanks for the information :-) On Sat, May 8, 2010 at 4:07 PM, Nikos Chantziaras rea...@arcor.de wrote: On 05/08/2010 09:21 PM, Crístian Viana wrote: hi everyone, something weird is happening on my system. I can't create new files, it says No space left on device, but the disk has several gigabytes of free space! The filesystem probably ran out of inodes. df -i /home will show inode usage. This can happen when you have many small files; they eat inodes but not storage space. -- alan dot mckinnon at gmail dot com -- alan dot mckinnon at gmail dot com
Re: [gentoo-user] Re: can't create file but disk isn't full
On 05/09/2010 01:39 AM, Crístian Viana wrote: I shutdown this computer everyday, those temp files shouldn't be alive for months. I ran lsof | grep deleted and it returned 132 lines, the biggest number being 2032226 (2 MB?), belonging to the Chromium browser process. even if every line had that value (which is not), that would sum up 264 MB, but the difference of reported/real free space is way bigger than that. changing the filesystem back to ext3 can solve this problem? it was ext3 before I've changed it to ext4 some months ago. On Sat, May 8, 2010 at 8:00 PM, Alan McKinnon alan.mckin...@gmail.com mailto:alan.mckin...@gmail.com wrote: You probably have files opened that have since been deleted. du doesn't report them as the names are no longer in the directory and df doesn't report them as they are pending deletion once the last handle to them is closed. It's a nasty thing to find. Run this: lsof | grep deleted You should find a ton of junk temp files (they will go away when you log out). Look for big numbers in column 8 On Sunday 09 May 2010 00:46:28 Crístian Viana wrote: it doesn't seem so :-( FilesystemInodes IUsed IFree IUse% Mounted on /dev/sda620856832 108698 207481341% /home I didn't know that the filesystem could run out of inodes before the disk space itself! thanks for the information :-) On Sat, May 8, 2010 at 4:07 PM, Nikos Chantziaras rea...@arcor.de mailto:rea...@arcor.de wrote: On 05/08/2010 09:21 PM, Crístian Viana wrote: hi everyone, something weird is happening on my system. I can't create new files, it says No space left on device, but the disk has several gigabytes of free space! The filesystem probably ran out of inodes. df -i /home will show inode usage. This can happen when you have many small files; they eat inodes but not storage space. -- alan dot mckinnon at gmail dot com this is unlikely, but can you create files as root? ext filesystems reserve a certain amount of space for root use only. you can change this with tune2fs if necessary.
[gentoo-user] Re: can't create file but disk isn't full
On 05/09/2010 01:46 AM, Crístian Viana wrote: it doesn't seem so :-( FilesystemInodes IUsed IFree IUse% Mounted on /dev/sda620856832 108698 207481341% /home I didn't know that the filesystem could run out of inodes before the disk space itself! thanks for the information :-) Long shot, but check if root can write files. If yes, it probably means your reserved block count is a bit high (default is 5% I believe). The reserved block count is a mechanism that disallows further writes to the filesystem if it gets too full, and only root can keep writing. If that's your problem, the reserved block count can be changed with the tune2fs tool. To set it to, say 2%, you would run: tune2fs -m 2 /dev/sda6 I don't know if it's safe to do this while the filesystem is mounted. To play it safe, go to single user mode, umount /home, and only then run the above command.
