Re: [dm-crypt] Computer locking up on heavy disk IO

[Arno Wagner <arno@wagner.name>]

Hi,

while I am really not an expert on ATA commands, this
looks like a dying disk, a dying disk controller or
bad cabeling to me. What happens is that your disk access 
fails and then it seems to go through a reset.  That pretty 
much kills performance.

I have no idea why this does not happen on normal access.
Is this perhaps on an old OCZ SSD? These use compression
and perform much worse with incompressible data.

Regards,
Arno

On Tue, Aug 01, 2017 at 22:22:11 CEST, heinrich5991@gmail.com wrote:
> On 08/01/17 11:57, Arno Wagner wrote:
> > Maybe your disk is dying or your CPU is inadequately cooled?
> > Or there is something else putting high load on your machine?
> 
> It really doesn't seem that one of these is the case, I performed these
> steps without any other open programs: After completely wiping the hard
> disk with the other method, I retried opening it with a random key in
> cryptsetup
> 
>   cryptsetup open --type plain -d /dev/urandom /dev/sdX sdX_wipe
> 
> and then overwriting it again
> 
>   pv /dev/zero > /dev/mapper/sdX_wipe
> 
> and after a couple of seconds, the computer locked up again. Does
> someone know how to debug this?
> 
> These dmesg entries look suspicious:
> 
> Aug 01 22:05:27 kernel: ata_piix 0000:00:1f.2: swiotlb buffer is full
> (sz: 61440 bytes)
> Aug 01 22:05:27 kernel: ata_piix 0000:00:1f.2: DMA: Out of SW-IOMMU
> space for 61440 bytes
> Aug 01 22:05:27 kernel: ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0
> action 0x0
> Aug 01 22:05:27 kernel: ata1.00: failed command: READ DMA EXT
> Aug 01 22:05:27 kernel: ata1.00: cmd 25/00:00:50:f5:53/00:01:bd:00:00/e0
> tag 0 dma 131072 in
>                                  res 50/00:00:4f:c1:3b/00:00:b8:00:00/e0
> Emask 0x40 (internal error)
> Aug 01 22:05:27 kernel: ata1.00: status: { DRDY }
> Aug 01 22:05:27 kernel: ata1.00: configured for UDMA/133
> Aug 01 22:05:27 kernel: ata1: EH complete
> Aug 01 22:05:27 kernel: ata_piix 0000:00:1f.2: swiotlb buffer is full
> (sz: 61440 bytes)
> Aug 01 22:05:27 kernel: ata_piix 0000:00:1f.2: DMA: Out of SW-IOMMU
> space for 61440 bytes
> Aug 01 22:05:27 kernel: ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0
> action 0x0
> Aug 01 22:05:27 kernel: ata1.00: failed command: READ DMA EXT
> Aug 01 22:05:27 kernel: ata1.00: cmd 25/00:00:50:f5:53/00:01:bd:00:00/e0
> tag 0 dma 131072 in
>                                  res 50/00:00:af:88:e0/00:00:e8:00:00/e0
> Emask 0x40 (internal error)
> Aug 01 22:05:27 kernel: ata1.00: status: { DRDY }
> [... a lot of repetitions of this]
> 
> Thanks
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-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
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