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Questions tagged [ext4]

The ext4 or fourth extended filesystem is a journaling file system for linux/*nix developed as the successor to ext3.

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How to hot backup/snapshot an ext4 partition (in the absence of LVM)?

I'm currently tasked with bringing up a existing server to (at least more) professional standards - with as little disruption as possible to end-users. To have a proper rollback, I need to backup the existing server's root fs, which is currently…
Roman
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Linux ext4 "extents" attribute

I noticed the e attribute on several files/directories on Linux machines installed on ext4 filesystems. [kelly@p2820887.pubip.serverbeach.com ~]$ lsattr -d /bin -------------e- /bin According to chattr(1): The ’e’ attribute indicates that the file…
tylerl
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How does the number of subdirectories impact drive read / write performance on Linux?

I've got an EXT3 formatted drive on a Linux CentOS server. This is a web app data drive and contains a directory for every user account ( there are 25,000 users ). Each folder contains files that that user has uploaded. Overall, this drive has…
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disk space overhead in ext4

I'd like to know if there's some rule (or formula) I can apply to find out how much of disk space will be used by the filesystem in an ext4 partition. for example, in a partition of 100 GB, how much can I actually use? does it depend on other…
cd1
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SSD TRIM (discard) problems with ext4 on Crucial C300 SSDs with CentOS 5.5

Playing around with using a modern kernel (2.6.37 currently) on an older OS (CentOS 5.5) so we can get TRIM (discard) working on our SSDs (Crucial C300s). The most recent hdparm (9.37) concurs that the C300 supports TRIM: ./hdparm -I /dev/sdc | grep…
Don MacAskill
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Options for performance improvements on very big Filesystems and high IOWAIT

I have a Ubuntu 16.04 Backup Server with 8x10TB HDD via a SATA 3.0 Backplane. The 8 Harddisks are assembled to a RAID6, an EXT4 Filesystem is in use. This Filesystem stores a huge amount of small files with very many SEEK operations but low IO…
t2m
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Remount root RW without reboot

Today I did something stupid on production xen vm server. I mounted the external device mapper as read only to make a copy of the filesystem. This process went well but then the rootfs / become read-only inside the guest machine. /dev/xvda on / type…
posixcompliant
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EXT4 performance has become really bad on system with lots of small files

I have a small embedded device that has only 128MB of RAM attached to this device is a 2TB USB2 hard disk I've been very happy with the performance of the device up until recently when either the number of files has cross a threshold of the capacity…
stuck
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Recovering a file with bad blocks in the middle

A large file on our ext4 file system may have picked up a bad block in the middle. Copying the file to another drive results in an input/output error part way through. Data beyond the bad sectors still seems ok though. We don't have a backup of…
Chris C.
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df reports wrong free space for an Ext4 partition

My system is CentOS 6 x86_64 with root partition formatted as ext4. df reports around 3Gb as used space: Filesystem 1K-blocks Used Available Use% Mounted on /dev/md1 20158260 3433724 15700540 18% / but du -sm -x /…
Alex
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fsck.ext4: How to force to check the whole file system?

It seems fsck.ext4 quit very soon, I guess it only checks the journal logs, and do nothing if the journal is clean. Is it? How to force it to check the whole file system? I've tried the -f option, but it quits again said it's clean very quickly.
Lenik
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Is ext4 ready for a production usage?

What do you think about ext4 filesystem in the production enviroment ? We are very close to launching our project that will use tens of millions quite often updated not very big files and we need to decide which FS to use. For a while our…
Konstantin
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ext4: Running out of inodes

I am running out of inodes. Only 11% available: the-foo:~ # df -i Filesystem Inodes IUsed IFree IUse% Mounted on /dev/mapper/system-home 9830400 8702297 1128103 89% /home Is there a way to solve this without creating and…
guettli
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5.5GB written daily to 1.2GB root volume - 4 times previous levels

Problem: I recently revamped one of my servers, it was tested prior to use, and functions well, however, a few days ago, I noticed approximately 4 times the usual amount of writes to the root volume. This is not a performance issue - the server runs…
cyberx86
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Causes of sudden massive filesystem damage? ("root inode is not a directory")

I have a laptop running Maverick (very happily until yesterday), with a Patriot Torx SSD; LUKS encryption of the whole partition; one lvm physical volume on top of that; then home and root in ext4 logical volumes on top of that. When I tried to boot…
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