Results 1 to 9 of 9

Thread: Is there a way to automatically reserve bad page frames?

  1. #1
    Join Date
    Jan 2018
    Location
    Annandale, VA
    Posts
    192

    Default Is there a way to automatically reserve bad page frames?

    I am getting a lot of single bit ECC failures at the same address. Is there a way to set a threshold for the number of failures, such that when the hits pass the threshold Linux will automatically move the page to a different page frame, or page it out, and then mark the bad page frame as permanently reserved?

  2. #2
    Join Date
    Jun 2008
    Location
    Podunk
    Posts
    28,090
    Blog Entries
    15

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by shmuelmetz View Post
    I am getting a lot of single bit ECC failures at the same address. Is there a way to set a threshold for the number of failures, such that when the hits pass the threshold Linux will automatically move the page to a different page frame, or page it out, and then mark the bad page frame as permanently reserved?
    Hi
    If you know the exact address you could look at the memmap kernel option to reserve/block it from use.

    https://www.kernel.org/doc/Documenta...parameters.txt

    Replace the RAM module, if you move to a different slot does the error move....?
    Cheers Malcolm °¿° SUSE Knowledge Partner (Linux Counter #276890)
    SUSE SLE, openSUSE Leap/Tumbleweed (x86_64) | GNOME DE
    If you find this post helpful and are logged into the web interface,
    please show your appreciation and click on the star below... Thanks!

  3. #3
    Join Date
    Jan 2018
    Location
    Annandale, VA
    Posts
    192

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by malcolmlewis View Post
    Hi
    If you know the exact address you could look at the memmap kernel option to reserve/block it from use.

    https://www.kernel.org/doc/Documenta...parameters.txt

    Replace the RAM module, if you move to a different slot does the error move....?
    Is memmap=1$ss legitimate?

    Editing /etc/sysctl.conf takes care of the one occurrence, but I was really hoping for a way to make it automatic for future occurrences.

  4. #4
    Join Date
    Jun 2008
    Location
    Podunk
    Posts
    28,090
    Blog Entries
    15

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by shmuelmetz View Post
    Is memmap=1$ss legitimate?

    Editing /etc/sysctl.conf takes care of the one occurrence, but I was really hoping for a way to make it automatic for future occurrences.
    Hi
    Alas my last and very limited experience with ECC memory was in the early 2000's on Solaris... check via dmesg | grep e820.
    Cheers Malcolm °¿° SUSE Knowledge Partner (Linux Counter #276890)
    SUSE SLE, openSUSE Leap/Tumbleweed (x86_64) | GNOME DE
    If you find this post helpful and are logged into the web interface,
    please show your appreciation and click on the star below... Thanks!

  5. #5
    Join Date
    Jan 2018
    Location
    Annandale, VA
    Posts
    192

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by malcolmlewis View Post
    Hi
    If you know the exact address you could look at the memmap kernel option to reserve/block it from use.

    https://www.kernel.org/doc/Documenta...parameters.txt
    What is the full parameter name in /etc/sysctl.conf and do I use memmap=1$0x000000002a7cb510, memmap=16$0x000000002a7cb510 or memmap=4K$x000000002a7cb000?

    Thanks.

  6. #6
    Join Date
    Jun 2008
    Location
    Podunk
    Posts
    28,090
    Blog Entries
    15

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by shmuelmetz View Post
    What is the full parameter name in /etc/sysctl.conf and do I use memmap=1$0x000000002a7cb510, memmap=16$0x000000002a7cb510 or memmap=4K$x000000002a7cb000?

    Thanks.
    Hi
    The last iteration so that would exclude 4K of memory starting at address 0x000000002a7cb000 (it is 0x too).
    Cheers Malcolm °¿° SUSE Knowledge Partner (Linux Counter #276890)
    SUSE SLE, openSUSE Leap/Tumbleweed (x86_64) | GNOME DE
    If you find this post helpful and are logged into the web interface,
    please show your appreciation and click on the star below... Thanks!

  7. #7
    Join Date
    Jan 2018
    Location
    Annandale, VA
    Posts
    192

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by malcolmlewis View Post
    Hi
    The last iteration so that would exclude 4K of memory starting at address 0x000000002a7cb000 (it is 0x too).
    Thanks. What name do I use for /proc or sysctl -w if I want to do it before a reboot?

  8. #8
    Join Date
    Jun 2008
    Location
    Podunk
    Posts
    28,090
    Blog Entries
    15

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by shmuelmetz View Post
    Thanks. What name do I use for /proc or sysctl -w if I want to do it before a reboot?
    Hi
    It should be down in /proc/sys/vm/.

    Have a read here: https://www.kernel.org/doc/Documentation/sysctl/vm.txt
    Cheers Malcolm °¿° SUSE Knowledge Partner (Linux Counter #276890)
    SUSE SLE, openSUSE Leap/Tumbleweed (x86_64) | GNOME DE
    If you find this post helpful and are logged into the web interface,
    please show your appreciation and click on the star below... Thanks!

  9. #9
    Join Date
    Jan 2018
    Location
    Annandale, VA
    Posts
    192

    Default Re: Is there a way to automatically reserve bad page frames?

    Quote Originally Posted by malcolmlewis View Post
    Hi
    It should be down in /proc/sys/vm/.

    Have a read here: https://www.kernel.org/doc/Documentation/sysctl/vm.txt
    That doesn't list memmap.

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •