Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.debian.user > #275343

Re: ext4 FS Crash

From Michael Stone <mstone@debian.org>
Newsgroups linux.debian.user
Subject Re: ext4 FS Crash
Date 2024-12-06 17:40 +0100
Message-ID <JQJx0-eeCN-9@gated-at.bofh.it> (permalink)
References (5 earlier) <JQo9b-dXPx-3@gated-at.bofh.it> <JQGz8-ebyf-15@gated-at.bofh.it> <JQH2a-ec1x-23@gated-at.bofh.it> <JQHbP-ecqG-5@gated-at.bofh.it> <JQIUh-ee9P-11@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Fri, Dec 06, 2024 at 10:51:20PM +0700, Max Nikulin wrote:
>Michael, thank you for the long message. Actually I wonder what is 
>"idle" that allows drive to perform self-maintenance. I expect that 
>the device should not be in some deep power saving state (I am yet to 
>discover available tunables that allows drive to "sleep"). Should it 
>be some period of time (seconds? minutes?) completely without any IO 
>or is it enough if read/write speed is below some threshold and 
>from/to another chip?

Basically it means that it isn't busy doing I/O; if you're reading or 
writing, the drive can't also be reading and writing. It doesn't need to 
be absolutely unused.

>As to erase block size, I am aware of it. On the other hand I am 
>surprised that a drive does not allow kernel to optimize writes on a 
>higher level (as uSD does):
>
>grep '' /sys/block/*/queue/discard_granularity
>...
>/sys/block/mmcblk0/queue/discard_granularity:4194304
>/sys/block/nvme0n1/queue/discard_granularity:4096
>/sys/block/sda/queue/discard_granularity:4096  # hdd (shingled)

The discard_granularity *limits* how the kernel can tell the drive that 
there are free blocks--a granularity of 4M means that the kernel can 
only issue a TRIM command when it has at least 4M of empty space *and* 
that empty space is aligned on a 4M boundary. (That is, you can't 
discard locations 2-5M on the drive, only 0-3M, 4-7M, etc.) It's a big 
number on the sd card because sd cards are pretty much junk. On a decent 
NVMe drive it'll typically be 512 (i.e., you can discard any logical 
block) or maybe 4096 if you're in 4k mode.

Back to linux.debian.user | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread


Thread

ext4 FS Crash Daniel Harris <mail.dharris@googlemail.com> - 2024-12-04 13:30 +0100
  Re: ext4 FS Crash Jochen Spieker <ml@well-adjusted.de> - 2024-12-04 13:50 +0100
  Re: ext4 FS Crash Eike Lantzsch ZP5CGE / KY4PZ <zp6cge@gmx.net> - 2024-12-04 15:40 +0100
    Re: ext4 FS Crash "Andrew M.A. Cater" <amacater@einval.com> - 2024-12-04 19:20 +0100
  Re: ext4 FS Crash "Alexander V. Makartsev" <avbetev@gmail.com> - 2024-12-04 17:30 +0100
  Re: ext4 FS Crash Klaus Singvogel <deb-user-ml@singvogel.net> - 2024-12-04 17:50 +0100
    Re: ext4 FS Crash Daniel Harris <mail.dharris@googlemail.com> - 2024-12-04 18:20 +0100
      Re: ext4 FS Crash Michael Stone <mstone@debian.org> - 2024-12-05 00:50 +0100
        Re: ext4 FS Crash Daniel Harris <mail.dharris@googlemail.com> - 2024-12-05 12:00 +0100
          Re: ext4 FS Crash Michael Stone <mstone@debian.org> - 2024-12-05 13:40 +0100
            Re: ext4 FS Crash Daniel Harris <mail.dharris@googlemail.com> - 2024-12-05 16:40 +0100
      Re: ext4 FS Crash Jörg-Volker Peetz <jvpeetz@web.de> - 2024-12-05 10:30 +0100
        Re: ext4 FS Crash Max Nikulin <manikulin@gmail.com> - 2024-12-05 16:30 +0100
          Re: ext4 FS Crash Erwan David <erwan@rail.eu.org> - 2024-12-05 16:40 +0100
            Re: ext4 FS Crash Andy Smith <andy@strugglers.net> - 2024-12-05 17:10 +0100
            Re: ext4 FS Crash gene heskett <gheskett@shentel.net> - 2024-12-06 02:00 +0100
          Re: ext4 FS Crash Michael Stone <mstone@debian.org> - 2024-12-05 18:50 +0100
            Re: ext4 FS Crash Jörg-Volker Peetz <jvpeetz@web.de> - 2024-12-06 14:30 +0100
              Re: ext4 FS Crash Michael Stone <mstone@debian.org> - 2024-12-06 15:00 +0100
                Re: ext4 FS Crash Jörg-Volker Peetz <jvpeetz@web.de> - 2024-12-06 15:10 +0100
                Re: ext4 FS Crash Max Nikulin <manikulin@gmail.com> - 2024-12-06 17:00 +0100
                Re: ext4 FS Crash Michael Stone <mstone@debian.org> - 2024-12-06 17:40 +0100
                Re: ext4 FS Crash Max Nikulin <manikulin@gmail.com> - 2024-12-08 17:30 +0100
                Re: ext4 FS Crash Michael Stone <mstone@debian.org> - 2024-12-08 18:20 +0100
                Re: ext4 FS Crash Max Nikulin <manikulin@gmail.com> - 2024-12-10 04:50 +0100
                Re: ext4 FS Crash Daniel Harris <mail.dharris@googlemail.com> - 2025-01-13 16:30 +0100
    Re: ext4 FS Crash Jeffrey Walton <noloader@gmail.com> - 2024-12-04 22:00 +0100
      Re: ext4 FS Crash Klaus Singvogel <deb-user-ml@singvogel.net> - 2024-12-05 08:30 +0100
        Re: ext4 FS Crash gene heskett <gheskett@shentel.net> - 2024-12-05 11:10 +0100
          Re: ext4 FS Crash Klaus Singvogel <deb-user-ml@singvogel.net> - 2024-12-05 13:10 +0100
            Re: ext4 FS Crash gene heskett <gheskett@shentel.net> - 2024-12-05 13:40 +0100
              Re: ext4 FS Crash Michael Stone <mstone@debian.org> - 2024-12-05 14:00 +0100
              Re: ext4 FS Crash Klaus Singvogel <deb-user-ml@singvogel.net> - 2024-12-05 15:00 +0100
                Re: ext4 FS Crash gene heskett <gheskett@shentel.net> - 2024-12-05 22:30 +0100
  Re: ext4 FS Crash Jeffrey Walton <noloader@gmail.com> - 2024-12-04 18:20 +0100

csiph-web