Re: Invalid optimal transfer size 33553920 accepted when physical_block_size 512

[Bernhard Sulzer <micraft.b@xxxxxxxxx>]

> >      # sg_readcap -l /dev/sdc
> >      Read Capacity results:
> >         Protection: prot_en=0, p_type=0, p_i_exponent=0
> >         Logical block provisioning: lbpme=0, lbprz=0
> >         Last LBA=15628053166 (0x3a3812aae), Number of logical
> > blocks=15628053167
> >         Logical block length=512 bytes
> >         Logical blocks per physical block exponent=3 [so physical block
> > length=4096 bytes]
> >         Lowest aligned LBA=0
> >      Hence:
> >         Device size: 8001563221504 bytes, 7630885.3 MiB, 8001.56 GB, 8.00 TB
> Please send me the output of:
>
> # sg_readcap /dev/sdc
>
> (i.e. without the -l from the previous run).
>
> I am very puzzled as to why we end up in the older capacity code for a
> device this big (8TB).

Here you go:

# sg_readcap /dev/sdc
READ CAPACITY (10) indicates device capacity too large
  now trying 16 byte cdb variant
Read Capacity results:
   Protection: prot_en=0, p_type=0, p_i_exponent=0
   Logical block provisioning: lbpme=0, lbprz=0
   Last LBA=15628053166 (0x3a3812aae), Number of logical blocks=15628053167
   Logical block length=512 bytes
   Logical blocks per physical block exponent=3 [so physical block 
length=4096 bytes]
   Lowest aligned LBA=0
Hence:
   Device size: 8001563221504 bytes, 7630885.3 MiB, 8001.56 GB, 8.00 TB

Hope this helps to solve it