Re: stalling IO regression since linux 5.12, through 5.18

Jan Kara
2022-08-17T18:16:03Z

On Wed 17-08-22 13:57:00, Chris Murphy wrote:
> On Wed, Aug 17, 2022, at 12:47 PM, Chris Murphy wrote:
> Can you boot with
> >> "megaraid_sas.host_tagset_enable = 0" kernel option and see whether the
> >> issue reproduces?
>
> This has been running an hour without symptoms. It's strongly suggestive,
> but needs to run overnight to be sure. Anecdotally, the max write IO is
> less than what I'm used to seeing.

OK, if this indeed passes then b6e68ee82585 ("blk-mq: Improve performance
of non-mq IO schedulers with multiple HW queues") might be what's causing
issues (although I don't know how yet...).

Honza

>
> [ 0.583121] Kernel command line: BOOT_IMAGE=(md/0)/vmlinuz-5.12.5-300.fc34.x86_64 root=UUID=04f1fb7f-5cc4-4dfb-a7cf-b6b6925bf895 ro rootflags=subvol=root rd.md.uuid=e7782150:092e161a:68395862:31375bca biosdevname=1 net.ifnames=0 log_buf_len=8M plymouth.enable=0 megaraid_sas.host_tagset_enable=0
> ...
> [ 6.745964] megasas: 07.714.04.00-rc1
> [ 6.758472] megaraid_sas 0000:02:00.0: BAR:0x1 BAR's base_addr(phys):0x0000000092000000 mapped virt_addr:0x00000000c54554ff
> [ 6.758477] megaraid_sas 0000:02:00.0: FW now in Ready state
> [ 6.770658] megaraid_sas 0000:02:00.0: 63 bit DMA mask and 32 bit consistent mask
> [ 6.795060] megaraid_sas 0000:02:00.0: firmware supports msix : (96)
> [ 6.807537] megaraid_sas 0000:02:00.0: requested/available msix 49/49
> [ 6.819259] megaraid_sas 0000:02:00.0: current msix/online cpus : (49/48)
> [ 6.830800] megaraid_sas 0000:02:00.0: RDPQ mode : (disabled)
> [ 6.842031] megaraid_sas 0000:02:00.0: Current firmware supports maximum commands: 928 LDIO threshold: 0
> [ 6.871246] megaraid_sas 0000:02:00.0: Performance mode :Latency (latency index = 1)
> [ 6.882265] megaraid_sas 0000:02:00.0: FW supports sync cache : No
> [ 6.893034] megaraid_sas 0000:02:00.0: megasas_disable_intr_fusion is called outbound_intr_mask:0x40000009
> [ 6.988550] megaraid_sas 0000:02:00.0: FW provided supportMaxExtLDs: 1 max_lds: 64
> [ 6.988554] megaraid_sas 0000:02:00.0: controller type : MR(2048MB)
> [ 6.988555] megaraid_sas 0000:02:00.0: Online Controller Reset(OCR) : Enabled
> [ 6.988556] megaraid_sas 0000:02:00.0: Secure JBOD support : No
> [ 6.988557] megaraid_sas 0000:02:00.0: NVMe passthru support : No
> [ 6.988558] megaraid_sas 0000:02:00.0: FW provided TM TaskAbort/Reset timeout : 0 secs/0 secs
> [ 6.988559] megaraid_sas 0000:02:00.0: JBOD sequence map support : No
> [ 6.988560] megaraid_sas 0000:02:00.0: PCI Lane Margining support : No
> [ 7.025160] megaraid_sas 0000:02:00.0: megasas_enable_intr_fusion is called outbound_intr_mask:0x40000000
> [ 7.025162] megaraid_sas 0000:02:00.0: INIT adapter done
> [ 7.025164] megaraid_sas 0000:02:00.0: JBOD sequence map is disabled megasas_setup_jbod_map 5707
> [ 7.029878] megaraid_sas 0000:02:00.0: pci id : (0x1000)/(0x005d)/(0x1028)/(0x1f47)
> [ 7.029881] megaraid_sas 0000:02:00.0: unevenspan support : yes
> [ 7.029882] megaraid_sas 0000:02:00.0: firmware crash dump : no
> [ 7.029883] megaraid_sas 0000:02:00.0: JBOD sequence map : disabled
> [ 7.029915] megaraid_sas 0000:02:00.0: Max firmware commands: 927 shared with nr_hw_queues = 1
> [ 7.029918] scsi host11: Avago SAS based MegaRAID driver
>
>
>
>
> --
> Chris Murphy
--
Jan Kara <jack@suse.com>
SUSE Labs, CR