18 replies to this topic

[Novac]

Hi
I have a VU Duo which I have just updated with the latest PLI version

I wonder which filesystem is used when I format my harddisk wia the menu options Harddisk ?

I have read somewere that ext2 is mutch faster that ext3.

Can I manualy format my disk to ext2 ?
If yes, how do the mount it correct, fx /hdd/movie ?

Thanks
Jan Larsen

[Erik Slagter]

I have read somewere that ext2 is mutch faster that ext3.

That's a complete hoax, forget it.

[MiLo]

It's using ext4 anyway.

[Novac]

Hi
Thanks for your answers...

/Jan Larsen

[MiLo]

If ext2 really were faster, we would have used that... That goes for most of these things, when in doubt about the best choice, just leave it at the default...

[Erik Slagter]

Also you don't want to use a non-journalling filesystem on a STB anyway...

[Jahu]

Ext2 is faster of course as it has no journaling and overheads, but ext4 is much better due to journaling as it removes the need for filesystem checks, stops file system fragmentation and speeds up boot.

So ext4 all the way.

[Erik Slagter]

Ext2 is faster in theory, but you won't see the difference, that's only when you run a high end database server. The journalling takes some extra processing and moving around of data, BUT you can minimise that if you only journal metadata (which is de default) and also journalling tends to speed up some operations as well. So the difference is really academic, almost nobody should be using ext2 anymore, and certainly not owners of stb'es.

[Trial]

Hi,
ext2 is also fast in practical use. Try recording one or two programs and then delete some files. Deleting is slow on ext3 and fast on ext2. Because of the journal you hardly will have consistency problems with ext3. Ext4 is again faster when deleting large files so it should be the best solution. I hesitate to switch to ext4 because there might be compatibility issues with other images.

Ralf

[greatred]

My personal experience with ext2 is very good. I`m using two partitions: first one beeing a 15Gb ext2 partition for timeshift recordings. The rest of the disc is used as a regular "recordings partition". The difference between ext2 and ext3 in regard of deleting files (that is what happen when one switch the channel while beeing in timeshift) is imho worth the hasel. But if anyone has some doubts about loosing some of the data - don`t use ext2.

[Erik Slagter]

When comparing ext2 and ext3, the difference is NOT the possible loss of data. If power gets interrupted or the box crashes, you WILL loose some data (if "something" is writing) without a doubt. The difference is the consistency in metadata. If you pull the plug on a ext2 filesystem, it will become corrupted. If you run fsck directly after that, you won't have much trouble, although you may have some "lost+found" files and you may loose some files. If you don't run fsck directly afterwards, the filesystem will become more and more corrupt onto a level where random files become corrupt or may corrupt other, existing files without a real reason. Ext3 always has consistent metadata, so you won't have this problem. So you really want to use at least ext3, even if it's slow at deleting files.

[WanWizard]

OpenPLi deletes recordings in the background, so slow deletes isn't really an argument for the use of ext2...

[greatred]

So you suggest to use higher ext FS even on the timeshift partition? I mean there is nothing I can lose in case of sudden power outage. Besides I really feel that an ext2 partition is more responsive when pressing the yellow Timeshift button - can this be possible or am I only blindly believing in this.
I`m eager to try ext4 on my sda2 partition used only for Timer Recordings and other media I upload to the box.

[Erik Slagter]

Please reread what I wrote earlier. It's not about the DATA it's all about the consistency of the METADATA, you really do not want to have a corrupt filesystem.

[greatred]

Thanks Erik, Now i get it. One time power loss can ruin not only the data stored on ext2 partition but the whole filesystem. This is clear now.
Not clear for me is how to mount ext4 on my DM800 with most current OpenPLi 2.1?
After mkfs.ext4 -L hdd /dev/sda2 I`m not able to mount the partition. Rebooting the box also didn`t helped.

EDiT:

nevermind, DM800 does not support ext4 filesystem.
That is what 'cat /proc/filesystems' is telling me

Edited by greatred, 15 January 2012 - 11:54.

[WanWizard]

Correct, you need to 3.x kernel for that, and DMM still can't deliver that, they're stuck on 2.6.18...

[Novac]

Hi Again
Interesting stuff to read.
I have now formated my disk with help of the Open Pli Menu options.
Everyting is fine.

When I want to copy back my backedup movies, it takes for ever....
I did the backup on a vista maschine and the data were apx. 250Gb

It has now been copieng for 12 hours and still misses 10 hours. Coping is done with 2Mb/s :-(
The vista PC and DUO are both connected with cable..and it seems like the DUO is the botlle neck, when I copy from my other maschine to my NAS, it does not take that long....

I just wonder why it takes so Long ??

/Jan L

[greatred]

Is your box in standby while copying the data? Also are you copying via FTP? On my DM800, with the box being in standby I can reach ~10Mb/s while copying with Filezilla.

[WanWizard]

Samba (CIFS) is notoriously slow on most STB's, due to the protocol overhead and the CPU limitations. FTP is indeed a much better option. NFS is quicker as well.