[LU-11200] Centos 8 arm64 server support

• Type: New Feature
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.14.0
• Affects Version/s: Lustre 2.12.0
• Assignee: James A Simmons
• Reporter: Oleg Drokin

Description

I am trying to bring up arm64 support for centos7 and it turns out centos 7 / rhel 7 for arm64 uses kernel 4.14 that we do not have any ldiskfs patches for.

I checked and the closest match is ubuntu18 4.15 kernel - the ldiskfs series has only a single trivial reject in ext4-data-in-dirent.patch

We also need a way to select it in configure that's a bit more complicated since I don't know how to do it easily yet.

Then there are compile errors:

/home/green/git/lustre-release/lustre/ptlrpc/../../lustre/ldlm/ldlm_lockd.c:135:74: error: macro "DEFINE_TIMER" requires 4 arguments, but only 2 given
 static CFS_DEFINE_TIMER(waiting_locks_timer, waiting_locks_callback, 0, 0);   
                                                                          ^

Issue Links

• is blocking: LU-12323 save_stack_trace_tsk is not exported on arm architectures
• is related to: LU-11224 T10PI assume several kernel features are enabled.
• is related to: LU-11832 ARM servers crashing on MDS startup
• is related to: LU-9793 sanity test 244 fail
• is related to: LU-11878 sanity test 103b: OOM because of too many bash processes: page allocation stalls for 18420ms
• is related to: LU-11246 New lustre e2fsprogs 1.44 issues
• is related to: LU-11440 Make e2fsprogs-1.44.3-wc1 release
• is related to: LU-12137 update client to use iterate_shared
• is related to: LU-10300 Can the Lustre 2.10.x clients support 64K kernel page?
• is related to: LU-11527 sanity test_270a failed with O_DIRECT on ARM
• is related to: LU-6387 Add Power8 support to Lustre
• is related to: LU-6766 add support for arm64

Comments

[Andreas Dilger]

The last patch for this ticket was landed in 2.14, and RHEL8 clients are working for all arches.

[Baptiste Gerondeau (Inactive)]

Thanks a lot !
Will take a look at it this week and report back (here I guess ? Let me know if I should open an issue/if there is a more "à propos" issue elsewhere)

[James A Simmons]

Baptiste I updated https://review.whamcloud.com/#/c/34714 This should make RHLE8 ARM fully functional.

[Baptiste Gerondeau (Inactive)]

I have tested out the latest lustre-release master on RHEL8 ARM64 VM and can confirm that it builds installs, runs and passes (most of) the sanity test suite with LDISKFS (in all-on-one-node configuration at the moment) !

Here are the results : results-ldiskfs-rhel8-2507.yml !
Will investigate further tomorrow, try to isolate the FAILS.

[Baptiste Gerondeau (Inactive)]

I have tested your patches against Fedora 30's 5.1.1 kernel, and the patches do not apply to the ext4.
I have also tested CentOS's 4.14.43-201 and the ialloc.c differs non trivially from what "rhel7.6alt/ext4-corrupted-inode-block-bitmaps-handling-patches.patch" expects.

I'd advise to use the upstream CentOS 7.6alt kernel : here which is the one you get doing a netinstall by default (if you don't run yum update afterwards).
The next to latest one is this one : here
For the latest one, kernel-alt-4.14.0-115.8.1.el7a, I can't seem to find the src rpm but here is the changelog : it doesn't seem to include any changes to EXT4 (only XFS).
I'll try to get a diff of 7.1 and 8.1's ext4 to make sure.

Concerning 7.6 vs RHEL8, I'm happy to test both.
Since the timeline to CentOS 8 is not clear, 7.6alt is still (the most) relevant (and since I haven't tested CentOS 8, there is no assurance it is as stable as 7.6alt yet).