search for: defragmentation

...lution to my issue below, but I''m curious as to what''s happening. Filefrag reports that a VM image file has 4744 extents. If I run btrfs fi defrag -v /path/to/file.vmdk, it returns immediately with no messages but an exit status of 20, and running filefrag again shows that no defragmentation has taken place. This is on Ubuntu 13.04, kernel 3.9.0-rc8 and v0.20-rc1 of the tools, and the file in the example is 34GB. Any ideas what''s happening here? Cheers, ---tim -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to...

...is nothing with the individual batches. The garbage collector do not seem to handle this (potential) fragmentation. Can the reason of the poor performance after a couple of iterations be that I'm fragmenting the memory? If so, is there a solution that can used to handle this within R, such as defragmentation or restarting R from within R? With kind regards M?ns Magnusson PhD Student, Statistics, Link?ping University. [[alternative HTML version deleted]]

...reallocated >to keep the data nearly contiguous. It's not perfect, but it works >fairly well and you should almost never see a performance >degradation caused by the filesystem's fragmentation. Is this statement accurate and does it mean ext2/3 is performing a sort of dynamic defragmentation? -- Maurice Volaski, mvolaski at aecom.yu.edu Computing Support, Rose F. Kennedy Center Albert Einstein College of Medicine of Yeshiva University

I've read in many places that file systems on Linux do not suffer the same fragmentation problems of Windows systems. No one has provided a clear explanation as to why fragmentation is not an issue for file systems such as ext2/3, reiserfs, xfs, etc. Just curious.

When designing a filesystem, is fragmentation really an issue if access to the disk can be done using scatter-gather DMA techics ?

A) Resilver = Defrag. True/false? B) If I buy larger drives and resilver, does defrag happen? C) Does zfs send zfs receive mean it will defrag? -- This message posted from opensolaris.org

...bits++; if (last_free_bits == move_len) { + i -= move_len; *goal_bit = i; *phys_cpos = base_cpos + i; break; @@ -1020,18 +1021,19 @@ int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp) context->range = ⦥ + /* + * ok, the default theshold for the defragmentation + * is 1M, since our maximum clustersize was 1M also. + * any thought? + */ + if (!range.me_threshold) + range.me_threshold = 1024 * 1024; + + if (range.me_threshold > i_size_read(inode)) + range.me_threshold = i_size_read(inode); + if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG)...

...bits++; if (last_free_bits == move_len) { + i -= move_len; *goal_bit = i; *phys_cpos = base_cpos + i; break; @@ -1020,18 +1021,19 @@ int ocfs2_ioctl_move_extents(struct file *filp, void __user *argp) context->range = ⦥ + /* + * ok, the default theshold for the defragmentation + * is 1M, since our maximum clustersize was 1M also. + * any thought? + */ + if (!range.me_threshold) + range.me_threshold = 1024 * 1024; + + if (range.me_threshold > i_size_read(inode)) + range.me_threshold = i_size_read(inode); + if (range.me_flags & OCFS2_MOVE_EXT_FL_AUTO_DEFRAG)...

Before I'd try to defragment my whole filesystem (see attached mail for whole story) I figured "Let's try it on some file". So I did > xfs_bmap /raid/Temp/someDiskimage.iso [output shows 101 extents and 1 hole] Then I defragmented the file > xfs_fsr /raid/Temp/someDiskimage.iso extents before:101 after:3 DONE > xfs_bmap /raid/Temp/someDiskimage.iso [output shows 3

Hello everybody, reading about the speed improvements possible with (on boot) preloaded files (which should be continuous on disk) I searched for a ext3 defrag program. I found an ext2 defrag program (http://www.ibiblio.org/pub/Linux/system/filesystems/defrag-0.70.tar.gz, available in debian as defrag) which would have an optimal feature (moving files by a list) but refuses to work on ext3.

Hi, I ran into a strange behavior with libvirt snapshots. I have some vms running with thin-provisioned qcow2 disk images (libvirt 1.1.3 with fedora 20). * When I create a snapshot on the VM, the qcow file suddenly grows big, somewhat bigger than the maximum size of the disk. * When I delete the snapshot, the allocated disk space is not freed up, the qcow image remains the same size. However, if

...ragmented for a long time. There are thus some empty areas reserved for new writes as well as for moving newly discovered WORM files to the WORM zones (free space permitting)... I wonder if this is viable with ZFS (COW and snapshots involved) when BP-rewrites are implemented? Perhaps such zoned defragmentation can be done based on block creation date (TXG number) and the knowledge that some blocks in certain order comprise at least one single file (maybe more due to clones and dedup) ;) What do you think? Thanks, //Jim Klimov

Hi, I use btrfs on most of my volumes on my laptop, and I''ve always felt booting was very slow, but definitely sure is slow, is starting up Google Chrome: encrypted ext4: ~20s btrfs: ~2:11s I have tried different things to find out exactly what is the issue, but haven''t quite found it yet. Here''s some stuff I got from latencytop, not sure if would be helpful:

I've been trying to figure out why some large files are taking a long time to rsync (80GB file). With this file, the match process is taking days. I've added logging to verbose level 4. The output from match.c is at the point where it is writing out the "potential match at" message. In a 9 hour period the match verbiage has changed from: potential match at 14993337175 i=2976

Hi! Is there plans for fragmentation analyzing/reporting and online defragmentation tools for btrfs? And what about delayed allocation? Thanks!

...llocate EF 3Mbit and BE 7Mbit in router. But using DREC (a receiver that comes with MGEN), i observed the bandwidth obtained by BE and EF do not tally with my tc configurations. And the sum of the total bandwidth received is about 4-5Mbps. I read somewhere in the mailing list that udp will have defragmentation problem. Another reason that i can guess is the way the software (MGEN and DREC) measure is not accurate. Any suggestions on what software i can use in order to have measurement that tally with tc configurations? Thanks. _____________________________________________________________________...

...OS: other Status: NEW Severity: normal Priority: P5 Component: iptables over nftable Assignee: pablo at netfilter.org Reporter: arnova at rocky.eld.leidenuniv.nl When using the iptables compatibility tools, creating rules for packet defragmentation result in incorrect rules. When eg. using "iptables-compat -A INPUT -f -j DROP" it results in "ip frag-off & 65311 == 0 ...." when it should be "ip frag-off != 0 .....". The same thing occurs when using iptables-compat restore|save. I can confirm this happens with...

I have a huge problem with ZFS pool fragmentation. I started investigating problem about 2 weeks ago http://www.opensolaris.org/jive/thread.jspa?threadID=34423&tstart=0 I found workaround for now - changing recordsize - but I want better solution. The best solution would be a defragmentator tool, but I can see that it is not easy. When ZFS pool is fragmented then: 1. spa_sync function is

On 12/08/2014 03:03 PM, Laszlo Hornyak wrote: > Hi, > > I ran into a strange behavior with libvirt snapshots. I have some vms > running with thin-provisioned qcow2 disk images (libvirt 1.1.3 with fedora > 20). > * When I create a snapshot on the VM, the qcow file suddenly grows big, > somewhat bigger than the maximum size of the disk. The maximum (guest) size of a disk is

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 zpool and zfs report different free space because zfs takes into account an internal reservation of 32MB or 1/64 of the capacity of the pool, what is bigger. So in a 2TB Harddisk, the reservation would be 32 gigabytes. Seems a bit excessive to me... - -- Jesus Cea Avion _/_/ _/_/_/ _/_/_/ jcea at jcea.es -