On 19.02.2022 12:02, Mike Karels wrote:
On 18 Feb 2022, at 20:55, Tomoaki AOKI wrote:
Just a thought, but can it be the reason with timing (e.g., rendezvous
within (i)threads, hardware controlls without using hardware timer)
problem?
On FreeBSD, IIUC, multi processor (multi core) implementation assumes
SMP (differs only clock speed) and end up with difference of
performance at same clock speed within P-core and E-core, possibly.
Another possibility is that the system is confused by having hyperthreading
on the P cores but not the E cores.
No, I've tried to disable SMT and different number of cores to make it
look identical and uniform for the scheduler. The only thing I could
not test is disabling all P cores to test only E, the motherboard does
not allow that, requiring at least one P core enabled.
BTW, how aarch64 guys implement big.Little support to avoid such a case?
Or are they simply disable all Little cores and use big only?
Are there supported arm64 systems with asymmetric processors yet?
Mike
On Fri, 18 Feb 2022 15:36:27 -0500
Alexander Motin <m...@freebsd.org> wrote:
This looks pretty weird to me, but I don't think it is specific to the
FAT32. Just today I've first noticed that booting TrueNAS 12.0-U8
(http://download.freenas.org/12.0/STABLE/U8/x64/TrueNAS-12.0-U8.iso)
(based on FreeBSD 12.2 with many backports) from NVMe SSD (I don't
insist on NVMe so far) and ZFS almost never completes successfully,
ending up in hangs or random stack corruption panics in ZFS threads as
soon as at least one E core is enabled of my i7-12700K. Disabling all E
cores fixes the problem. Updated to TrueNAS 13.0-BETA1 (based on
FreeBSD 13.0-STABLE from few weeks ago) it does not demonstrate the
problem any more. The same TrueNAS 12.0-U8 kernel booted from NFS does
not seem to demonstrate the problem with ZFS mounting, but I haven't
stressed it much so far.
There are seem to be dragons somewhere...
On 15.02.2022 22:29, Chen, Alvin W wrote:
Hi Guys,
Any updates to support Intel P-core + E-core?
I have filed a bug: PR 261169
<https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=261169> , but no updates.
Does anybody know the progress?
For Intel Adler Lake P core + E core processor (i7-12700T), copying
files to FAT32 partition, the file corrupted (50%), but ZFS is fine.
After disabling E core in the code by restrict the max cpu number, this
issue is gone. And No E core processor has no such issue, like i7-12400.
HW ENV:
CPU: Intel AlderLake 12th Gen i7-12700T
Disk: NVME SSD
There are 3 methods to reproduce this issue:
1. Make FreeBSD 13 USB disk installer, install FreeBSD with UFS, and
select install source and ports, the txz package checking will be failed.
2. Boot to shell by USB disk installer, and mount a FAT32 partition (on
SSD), and copy a 300MB file to the FAT32, compare the sha256 checksums
for the source file and the dst file, the checksum are different (50%).
Or if there is a 300MB file in FAT32 partition, mount the partition, and
for the first time check the sha256 value by running 'sha256 file.tgz',
the checksum is wrong, but the second time, the checksum is correct.
3. Install FreeBSD 13 with ZFS, and it can work well. And boot into
FreeBSD, disable swap, and format the SWAP partition to FAT32. Do the
testing as above.
Regards,
Alvin Chen
Dell | Comercial Client Group
office +86-10-82862506, fax +86-10-82861554, Dell Lync 8672506
weike_c...@dell.com <mailto:weike_c...@dell.com>
Internal Use - Confidential
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Alexander Motin
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青木 知明 [Tomoaki AOKI] <junch...@dec.sakura.ne.jp>
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Alexander Motin
