1
vote
0answers
20 views

Ext4 allocation pattern with random writes in sparse file

If I create a large (a few GB) sparse file in ext4, and then write randomly throughout the length until all 4k blocks have been "touched", in the absence of other heavy write load, can I expect that ...
4
votes
3answers
102 views

Can a large number of (small) files degrade the performance of a filesystem?

I'm working on an archival project and currently I'm storing 514600 images (ranging from 200kb to 2mb) on my 4TB NAS drive. The drive itself is formatted as ext4 and I'm writing the files over the ...
1
vote
0answers
19 views

ext4 superblock checksum?

I'm reading the ext4 superblock, but its s_checksum (offset 0x3FC) is always zero. Also the s_checksum_type (offset 0x175) field is zero as well, however according to ...
3
votes
2answers
173 views

Is there anything faster than `find . | wc -l` to count files in a directory?

Not uncommonly I have to count the number of files in a directory, sometimes this runs into the millions. Is there a better way than just enumerating and counting them with find . | wc -l ? Is there ...
1
vote
1answer
67 views

ext3 vs ext4 bonnie++ rand/seq create speed

I am testing the difference between ext3 and ext4 for our application. When I run both filesystems through a bonnie++ test, the results for file creation on ext4 aren't very good. While ext3 can ...
1
vote
1answer
26 views

EXT and other filesystems

Is it true only NTFS needs to be defragmented? Are filesystems like ext4, 3 and 2 immune to fragmentation issues. Apple never seems to require a defragmentation so what makes some filesystems immune ...
1
vote
0answers
157 views

Contiguous physical allocation of a set of files in linux filesystem (ext4)

I have a set of files that I wish to be allocated contiguously in the filesystem. I will be accessing all these files sequentially in a single read one after the other and I want to optimize reading ...
0
votes
1answer
149 views

EXT4 external hard drive for use with multiple systems

I recently bought a external hard drive to store some data on. I use Linux but I am not a power user. If I format the drive to EXT4, is it possible for the permissions to ever screw up and I lose ...
0
votes
0answers
41 views

Can grep read filenames from partially formatted filesystem?

Quick Explanation I accidentally partially (ripped the cord out when it started) formatted an ext4 partition via Ubuntu Disk Utility GUI as ext4. Presumably via mkfs or mke2fs or however it does it ...
0
votes
1answer
30 views

A file system operation that would incur a seek/rotational cost

I am looking to generate a workload that will do operations on a file system that will make the disk access to have rotational or seeking cost. Env details: partition size: 30 G. File system : ...
3
votes
2answers
13k views

Creating ext4 partition from console

I have a volume /dev/sda1 (1.2 TB) containing an NTFS partition using 0.6 TB space. I want to make an ext4 partition in the remaining 0.6 TB space. I have not tried anything yet because I don't want ...
0
votes
0answers
87 views

cloning a HD using dd: can this cause filesystem problems using ext4?

Background: hard drive A has a large LVM partition inside which a number of Ext4 filesystems live. hard drive B is of a different make/model and of larger size. Questions: If I image (using dd) ...
0
votes
1answer
185 views

e2image restore file system metadata

I'm trying to recreate file system metadata on a virtual disk. I can save this metadata using e2image, and the e2image man page tells me I can use e2image -I to restore the file system. Unfortunately, ...
1
vote
1answer
89 views

Attributes of a file - followup for Windows and Linux

I found a question that lists the (quote): attributes are of a regular file (as opposed to a symbolic link, etc.) on Mac OS X with Mac OS Extended (Journaled) (HFS+) Does such a list exist for ...
0
votes
2answers
83 views

How to analyse timestamp in ext4 manually?

I am doing research on Ext4 and I believe I understand the fundamentals of Ext4. Ext4 stores timestamps. In my assignment, I have proposed to analyse the timestamp of Ext4 MANUALLY instead of typing ...
2
votes
2answers
1k views

Will a EXT4 Samba Share be readable by Windows/Mac OS X users?

If I share my ext4 drive by SMB will a Windows/OSX user be able to read/write to it WITHOUT installing additional drivers to their machine?
0
votes
1answer
707 views

eMMC Standards and File System support

I am looking into Android secure erase functions and realized a few things: Android uses eMMC as its storage media, eMMC standards are set by the JEDEC organization (currently most of the ...
0
votes
1answer
129 views

How does the number of files in the same folder affect I/O performance in an ext4 filesystem

I'm using Kyoto Cabinet (a key-value store) for my project. The specific type of DB I'm using is DirDB which creates a lot of files in a directory to store the key-value pairs. The server I'm running ...
2
votes
2answers
7k views

How do I read the Ext4 partition of my SD card on Windows? [duplicate]

I have a 32 GB SD card with one FAT32 partition and one Ext4 partition. If I mount the SD card to the computer I can read the FAT32 partition in Windows just fine. But how do I read the Ext4 ...
1
vote
2answers
113 views

I have an ext3 iso disk image. Can I use it and write it to a ext4 partition?

Is it possible to do so ? I am migrating to EXT4 because of the SSD drive that has TRIM funtion. I have to have ext4 partion.
2
votes
1answer
340 views

ext4 integration in windows 8 - access through explorer

I know there are similar questions; however none I could find that addressed accessing ext4 through explorer, most others simply use a third party application. However, my question is; is there a way ...
5
votes
2answers
5k views

Do ext4 filesystems need to be defragmented?

Do ext4 filesystems need to be defragmented? If so, how do I defragment them? If not, could you post a simple explanation of why they do not need to be defragmented?
2
votes
1answer
6k views

Disable journaling on ext4 filesystem partition

I'm running Linux Mint on an SSD. I've read how one optimization is to disable journaling. However, when I run the command: sudo mke2fs -t ext4 -O ^has_journal /dev/sda1 I get an error saying that ...
1
vote
2answers
354 views

Why doesn't Ext4 cache directory size?

Once again I'm cleaning up my desktop because I'm running out of HDD space and everytime I call 'du -sh ~', it takes a really long time to calculate the current size of the directory. From my ...
2
votes
1answer
2k views

What is EXT4-fs error (device md0): ext4_mb_generate_buddy:739: group 10770, 0 clusters in bitmap, 32768?

On my Ubuntu Server 12.04 I got this errors (via dmesg): [ 1104.544121] EXT4-fs error (device md0): ext4_mb_generate_buddy:739: group 10771, 0 clusters in bitmap, 32768 in gd [ 1104.549227] EXT4-fs ...
2
votes
1answer
152 views

Is file creation durable on ext4?

On some filesystems, when creating a file, it is necessary to call fsync() not only on the file itself, but also on the parent directory, to make the file creation durable. Otherwise, the directory ...
1
vote
2answers
4k views

How long can file system writes be cached with ext4?

A while ago, there has been some discussion about ext4 potentially leaving empty files after an unclean unmount, summed up pretty well in this article. Basically, because of delayed allocation, writes ...
0
votes
1answer
367 views

zram trimming by writing zero pages

I'm using ZRAM as a backing block device for /tmp filesystem in the following manner: echo 8000000000 > /sys/block/zram0/disksize mkfs.ext4 -O ...
1
vote
1answer
265 views

EXT4-fs error (device loop0) ext4_mb_generate_buddy

I've been randomly getting theses in my /var/log/messages [5747511.945300] EXT4-fs error (device loop0): ext4_mb_generate_buddy: EXT4-fs: group 1: 29505 blocks in bitmap, 29455 in gd Not had any ...
0
votes
1answer
88 views

Quick way to empty a partition

I have a partition, formatted ext4, that I want to empty completely. I will be repeating this write-then-empty process repeatedly, so I want the emptying step to be as quick as possible. One option ...
1
vote
1answer
2k views

Is there a tool to browse files on a VMware virtual disk w/o starting a virtual machine?

I am looking for a way to browse through a VMware virtual disk in order to extract/copy files that are located on an Ubuntu EXT4 partition that is allocated on that disk, without the need to actually ...
0
votes
1answer
80 views

Dealing with different usernames when mounting removable media in Linux

I have a laptop in which my username is, say, "foo". I have an external drive, formatted with Ext4, for which all files are owned by "foo" (at a filesystem level). Now, I have a desktop in which my ...
0
votes
1answer
4k views

Unable to repair an ext4 filesystem with bad superblock

Using the dd command, I was hoping that I would be able to copy over the first 446 bytes from Disk B (250GB) to Disk A (80GB), in order to make Disk A bootable just like Disk B. I issued the command: ...
1
vote
2answers
181 views

Drive system file size

When i made a new drive it take some space for system file FAT32 take the less space, then NTFS, then ext4 my question how to know the space will be taken for the system before make the drive, if the ...
4
votes
2answers
3k views

how to convert NTFS to ext4 in windows?

I want to convert one partition of my windows which is NTFS (or can be FAT32) to a linux file system partitioning? I'm looking for some tools or ways to do it for me!
8
votes
2answers
5k views

SSD: NTFS vs EXT4

Always when I read about SSD usage under Linux, the advice is to disable journalling in Ext4 (or use Ext2), since it's too bad for your SSD. But in all articles about SSD tweaks for Windows, I never ...
1
vote
1answer
369 views

Recommendations for Filesystem

I have built the bones of a NAS system (which comprises of Ubuntu server 11.04 on 500GB SATA drive, and 3 2TB SATA disks in software RAID5 configuration)... I'm looking for some advice on what ...
7
votes
5answers
8k views

Stuck choosing between ext4 and ext3 for the file system

I was in the process of installing Ubuntu 11.10, but got stuck choosing which file system to use. ext3 and ext4; which is better for a personal desktop? If ext4 is better, will it work well on my ...
8
votes
5answers
3k views

Is ext4 more expensive than ntfs?

I have just converted an NTFS partition to ext4, however the total space seems reduced from 421G to 415G. Where did the 6G go? And, the reserved space is grown to 199M in ext4, much larger compared to ...
3
votes
1answer
3k views

resize2fs seems stuck at pass 3 (scanning inode table) - what to do?

I have a machine running Arch Linux (2010, I believe) with a 6TB RAID-5 array hooked up to a Highpoint RocketRaid 2320. I've been having issues with the RAID controller's drivers and the latest Linux ...
1
vote
1answer
278 views

Identical hard drives with different sizes (formatting)

I have two hard drives, which are identical, same model though purchased at different times, but in all respects the same. Afaik the manufacturer hasn't changed capacity (Seagate expansion). However, ...
4
votes
1answer
725 views

What filesystem should I use for a large amount of disk space in Linux (>32TB)?

I am trying to make a large file system in linux, but have run into problems with many of the common file systems. JFS has a bug that does not allow expansion over 32TB. XFS has a bug in the fsck ...
1
vote
1answer
812 views

Encryption, loop device and journaling file system on Linux

I've been reading up on tools like Truecrypt, loop-AES and Cryptoloop that use a "loop device" to create an encrypted disk volume within a file. On the README page for loop-AES, it has this paragraph ...
9
votes
2answers
7k views

Why is an Ext4 disk check so much faster than NTFS?

I had a situation today where I restarted my computer and it said I needed to check the disk for consistancy. About 10 minutes later (at "1%" complete), I gave up and decided to let it run when I go ...
1
vote
2answers
6k views

mounting ext4 fs with block size of 65536

I am doing some benchmarking on EXT4 performance on Compact Flash media. I have created an ext4 fs with block size of 65536. however I can not mount it on ubuntu-10.10-netbook-i386. (it is already ...
1
vote
1answer
174 views

Questions about solid state drives?

How to tell if a hard drive is solid state drive? For example: For one laptop, its hard drive is 244GB Western Digital WDC WD2500BEVS-08VAT2 (SATA) For another, its hard drive is 98GB ...
7
votes
2answers
219 views

Which ext4 features are missing on an upgraded filesystem?

Which ext4 features will be missing on a filesystem upgraded from ext3 to ext4 using the instructions here? The text explains: There are additional ext4 features, such as flex_bg and > 16TB ...
1
vote
1answer
1k views

Upgrade root (also boot) filesystem from ext3 to ext4 on Debian

After upgrading a Debian system from 5.0 to 6.0 (Lenny to Sqeeze), how do I go about upgrading the root filesystem (which in this case is also boot) from ext3 to ext4?
3
votes
2answers
347 views

Invalid size displayed for SSD

I have an 80GB Intel X25-M SSD drive installed on a Linux box running Debian 5.0. The file system on the SSD is ext4. I've had no problems with the drive, and have been using it for quite some time ...
1
vote
2answers
115 views

Is it possible to restore a backup on different filesystems?

I'm now using Ubuntu 10.04 with ext4 and for the second time in my life I experienced data loss (not for real: I got backups) and I'm assuming problems with the recent ext4 fs. I want to restore all ...