ubifs mount size
Does this look right (info below) ?
I create a 55MiB volume, but df only shows 33968KiB This is linux-2.6.24.4. I've also used linux-2.6.27-rc3.
root@tsi-sa2410:~# ubimkvol /dev/ubi1 -N root -s 55MiB Volume ID 0, size 3755 LEBs (57676800 bytes, 55.0 MiB), LEB size 15360 bytes (15.0 KiB), dynamic, name "root", alignment 1 root@tsi-sa2410:~# mount -t ubifs ubi1:root /mnt/linux2-root/ UBIFS: default file-system created UBIFS: background thread "ubifs_bgt1_0" started, PID 930 UBIFS: mounted UBI device 1, volume 0, name "root" UBIFS: file system size: 57292800 bytes (55950 KiB, 54 MiB, 3730 LEBs) UBIFS: journal size: 2872320 bytes (2805 KiB, 2 MiB, 187 LEBs) UBIFS: default compressor: LZO UBIFS: media format 4, latest format 4 root@tsi-sa2410:~# df Filesystem 1k-blocks Used Available Use% Mounted on rootfs 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% /dev/.static/dev ubi1:root 33968 0 31204 0% /mnt/linux2-root
Quoted 5 lines · dfoley
Does this look right (info below) ?
I create a 55MiB volume, but df only shows 33968KiB This is linux-2.6.24.4. I've also used linux-2.6.27-rc3.
Quoted 16 lines
root@tsi-sa2410:~# ubimkvol /dev/ubi1 -N root -s 55MiB Volume ID 0, size 3755 LEBs (57676800 bytes, 55.0 MiB), LEB size 15360 bytes (15.0 KiB), dynamic, name "root", alignment 1 root@tsi-sa2410:~# mount -t ubifs ubi1:root /mnt/linux2-root/ UBIFS: default file-system created UBIFS: background thread "ubifs_bgt1_0" started, PID 930 UBIFS: mounted UBI device 1, volume 0, name "root" UBIFS: file system size: 57292800 bytes (55950 KiB, 54 MiB, 3730 LEBs) UBIFS: journal size: 2872320 bytes (2805 KiB, 2 MiB, 187 LEBs) UBIFS: default compressor: LZO UBIFS: media format 4, latest format 4 root@tsi-sa2410:~# df Filesystem 1k-blocks Used Available Use% Mounted on rootfs 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% /dev/.static/dev ubi1:root 33968 0 31204 0% /mnt/linux2-root
Yes this looks right. UBIFS doesn't really know how much data can be fitted in the file system, so it makes a worst case estimate.
Hi,
Quoted 24 lines · Adrian Hunter
Quoted 14 lines · dfoley
Does this look right (info below) ?
I create a 55MiB volume, but df only shows 33968KiB This is linux-2.6.24.4. I've also used linux-2.6.27-rc3.root@tsi-sa2410:~# ubimkvol /dev/ubi1 -N root -s 55MiB Volume ID 0, size 3755 LEBs (57676800 bytes, 55.0 MiB), LEB size 15360 bytes (15.0 KiB), dynamic, name "root", alignment 1 root@tsi-sa2410:~# mount -t ubifs ubi1:root /mnt/linux2-root/ UBIFS: default file-system created UBIFS: background thread "ubifs_bgt1_0" started, PID 930 UBIFS: mounted UBI device 1, volume 0, name "root" UBIFS: file system size: 57292800 bytes (55950 KiB, 54 MiB, 3730 LEBs) UBIFS: journal size: 2872320 bytes (2805 KiB, 2 MiB, 187 LEBs)Quoted 8 lines
UBIFS: default compressor: LZO UBIFS: media format 4, latest format 4 root@tsi-sa2410:~# df Filesystem 1k-blocks Used Available Use% Mounted on rootfs 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% /dev/.static/dev ubi1:root 33968 0 31204 0% /mnt/linux2-root
Quoted 2 lines
Yes this looks right. UBIFS doesn't really know how much data can be fitted in the file system, so it makes a worst case estimate.
In practice you will be able to fit more than what df shows. I will write a corresponding FAQ entry which will explain the issue later.
Signature · 2 lines
Best regards, Artem Bityutskiy (Битюцкий Артём)
Quoted 2 lines
Quoted 2 lines
Yes this looks right. UBIFS doesn't really know how much data canbe
fitted
Quoted 5 lines
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in the file system, so it makes a worst case estimate.
In practice you will be able to fit more than what df shows. I will write a corresponding FAQ entry which will explain the issue later.
Oh good. I finally have my 8GiB problem solved (patch forthcoming in the next 24 hours probably), but df -h was only showing 6.8GiB and I couldn't account for the descrpancy. I'm looking forward to being able to do that.
Thanks for all the hard work on UBI/UBIFS Artem. It's working like a champ so far. I'm planning on setting LTP up to run for a couple of weeks to really stress it out and I'll let you know how that goes.
FYI, it takes about 45 seconds for the UBI module to load for an 8GiB device when I do it by hand. I think things were a bit faster when UBI is built into the kernel. Once I get that working again I'll update you.
Bruce
Hello dfoley, Bruce,
Quoted 14 lines · dfoley
Does this look right (info below) ?
I create a 55MiB volume, but df only shows 33968KiB This is linux-2.6.24.4. I've also used linux-2.6.27-rc3.root@tsi-sa2410:~# ubimkvol /dev/ubi1 -N root -s 55MiB Volume ID 0, size 3755 LEBs (57676800 bytes, 55.0 MiB), LEB size 15360 bytes (15.0 KiB), dynamic, name "root", alignment 1 root@tsi-sa2410:~# mount -t ubifs ubi1:root /mnt/linux2-root/ UBIFS: default file-system created UBIFS: background thread "ubifs_bgt1_0" started, PID 930 UBIFS: mounted UBI device 1, volume 0, name "root" UBIFS: file system size: 57292800 bytes (55950 KiB, 54 MiB, 3730 LEBs) UBIFS: journal size: 2872320 bytes (2805 KiB, 2 MiB, 187 LEBs)
Quoted 8 lines
UBIFS: default compressor: LZO UBIFS: media format 4, latest format 4 root@tsi-sa2410:~# df Filesystem 1k-blocks Used Available Use% Mounted on rootfs 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% /dev/.static/dev ubi1:root 33968 0 31204 0% /mnt/linux2-root
I've explored this a little. Currently UBIFS indeed reports 15%-20% less free space than it actually has, and we'll try to fix this.
However, even if we fix this, it'll still report less free space than it has. I have started writing about this here:
http://www.linux-mtd.infradead.org/doc/ubifs.html
I did not finish my writing yet, and I did not actually write the stuff which is mostly relevant for your situation. But I wrote other df-related stuff which UBIFS users should probably know about.
One thing I may say about your setup is that you have small eraseblock size (16KiB) which leads to large mistakes in calculations because the maximum amount of wasted space at the end of eraseblock is large in your case.
Quoted 6 lines · On Mon, 2008-08-18 at 16:32 -0700, [email protected] wrote:
Oh good. I finally have my 8GiB problem solved (patch forthcoming in the
next 24 hours probably), but df -h was only showing 6.8GiB and I couldn't
account for the descrpancy. I'm looking forward to being able to do that.
Similarly, we will try to make improve the free space reporting, but it'll lie anyway, but less.
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Thanks for all the hard work on UBI/UBIFS Artem. It's working like a champ so far. I'm planning on setting LTP up to run for a couple of weeks
to really stress it out and I'll let you know how that goes.
Thank you. But I was not the only person working on UBIFS. Adrian implemented bigger part of it than me.
Stress tests are appreciated and posting the results here is welcomed.
Quoted 4 lines
FYI, it takes about 45 seconds for the UBI module to load for an 8GiB device when I do it by hand. I think things were a bit faster when UBI is
built into the kernel. Once I get that working again I'll update you.
Yeah, bad. One straight way to make it twice as fast is to merge 128KiB physical eraseblocks to 265KiB ones. Then UBI would read twice as less. And I wouldn't be surprised if UBIFS would become faster.
I mean, you could hack your NAND driver and teach it to join 2 physical eraseblocks into one, and make all upper layers think you have 256KiB eraseblocks. Things would become tricky for bad blocks, and you effectively would treat good PEBs as bad if their pair is bad. But is probably is not so bad, comparing to twice as faster UBI attach time. And you would win the space you wasted because of bad blocks by wasting less space in both UBI and UBIFS.
Signature · 2 lines
Best regards, Artem Bityutskiy (Битюцкий Артём)
Quoted 3 lines · Artem Bityutskiy
However, even if we fix this, it'll still report less free space than it has. I have started writing about this here:
http://www.linux-mtd.infradead.org/doc/ubifs.html
As usually, I apologize for my English and appreciate any spelling/bad phrasing fixes.
Signature · 2 lines
Best regards, Artem Bityutskiy (Битюцкий Артём)
Hi,
Quoted 18 lines · Artem Bityutskiy
Quoted 9 lines
root@tsi-sa2410:~# ubimkvol /dev/ubi1 -N root -s 55MiB Volume ID 0, size 3755 LEBs (57676800 bytes, 55.0 MiB), LEB size 15360 bytes (15.0 KiB), dynamic, name "root", alignment 1 root@tsi-sa2410:~# mount -t ubifs ubi1:root /mnt/linux2-root/ UBIFS: default file-system created UBIFS: background thread "ubifs_bgt1_0" started, PID 930 UBIFS: mounted UBI device 1, volume 0, name "root" UBIFS: file system size: 57292800 bytes (55950 KiB, 54 MiB, 3730 LEBs) UBIFS: journal size: 2872320 bytes (2805 KiB, 2 MiB, 187 LEBs)Quoted 8 lines
UBIFS: default compressor: LZO UBIFS: media format 4, latest format 4 root@tsi-sa2410:~# df Filesystem 1k-blocks Used Available Use% Mounted on rootfs 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% /dev/.static/dev ubi1:root 33968 0 31204 0% /mnt/linux2-root
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I've explored this a little. Currently UBIFS indeed reports 15%-20% less free space than it actually has, and we'll try to fix this.
We have improved UBIFS free space reporting and it should be much better now. Please, pull master branch of the ubifs-2.6.git tree to find the fixes.
Signature · 2 lines
Best regards, Artem Bityutskiy (Битюцкий Артём)
Quoted 19 lines · Artem Bityutskiy
Hi,
Quoted 16 lines · Artem Bityutskiy
Quoted 16 lines
root@tsi-sa2410:~# ubimkvol /dev/ubi1 -N root -s 55MiB Volume ID 0, size 3755 LEBs (57676800 bytes, 55.0 MiB), LEB size 15360 bytes (15.0 KiB), dynamic, name "root", alignment 1 root@tsi-sa2410:~# mount -t ubifs ubi1:root /mnt/linux2-root/ UBIFS: default file-system created UBIFS: background thread "ubifs_bgt1_0" started, PID 930 UBIFS: mounted UBI device 1, volume 0, name "root" UBIFS: file system size: 57292800 bytes (55950 KiB, 54 MiB, 3730 LEBs) UBIFS: journal size: 2872320 bytes (2805 KiB, 2 MiB, 187 LEBs) UBIFS: default compressor: LZO UBIFS: media format 4, latest format 4 root@tsi-sa2410:~# df Filesystem 1k-blocks Used Available Use% Mounted on rootfs 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% / /dev/root 8059 5284 2366 69% /dev/.static/dev ubi1:root 33968 0 31204 0% /mnt/linux2-root
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I've explored this a little. Currently UBIFS indeed reports 15%-20% less free space than it actually has, and we'll try to fix this.
We have improved UBIFS free space reporting and it should be much better now. Please, pull master branch of the ubifs-2.6.git tree to find the fixes.
Yes, looks good now.
I'm now using a different size nand device (128MiB, 2KiB page size). 2 partitions in the driver as (16MiB, and 112MiB), which I've just mapped 1:1 with ubimkvol (ie. ubimkvol /dev/ubi0 -N boot -m and ubimkvol /dev/ubi1 -N root -m)
root@Linux tsi-tpcxx 2.6.27-rc5-next-20080905 #1 Wed Sep 10 02:22:05 UTC
2008 armv4tl unknowntsi-tpcxx:~# df
Filesystem 1k-blocks Used Available Use% Mounted on
rootfs 102744 13096 84588 13% / ubi1:root 102744 13096 84588 13% / ubi0:boot 12916 1692 10520 14% /boot