Re: [PATCH] block/nvme: Add driver statistics for access alignment and hw errors

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

On 10/1/20 11:59 AM, Stefan Hajnoczi wrote:
> On Wed, Sep 30, 2020 at 03:36:17PM +0200, Philippe Mathieu-Daudé wrote:
>>     "return": [
>>         {
>>             "device": "",
>>             "node-name": "drive0",
>>             "stats": {
>>                 "flush_total_time_ns": 6026948,
>>                 "wr_highest_offset": 3383991230464,
>>                 "wr_total_time_ns": 807450995,
>>                 "failed_wr_operations": 0,
>>                 "failed_rd_operations": 0,
>>                 "wr_merged": 3,
>>                 "wr_bytes": 50133504,
>>                 "failed_unmap_operations": 0,
>>                 "failed_flush_operations": 0,
>>                 "account_invalid": false,
>>                 "rd_total_time_ns": 1846979900,
>>                 "flush_operations": 130,
>>                 "wr_operations": 659,
>>                 "rd_merged": 1192,
>>                 "rd_bytes": 218244096,
>>                 "account_failed": false,
>>                 "idle_time_ns": 2678641497,
>>                 "rd_operations": 7406,
>>             },
>>             "driver-specific": {
>>                 "driver": "nvme",
>>                 "completion-errors": 0,
>>                 "unaligned-access-nb": 2959,
>>                 "aligned-access-nb": 4477
> 
> "nb" is number?

Yes:

 # @aligned-access-nb: The number of aligned accesses performed by
 #                     the driver.
 #
 # @unaligned-access-nb: The number of unaligned accesses performed by
 #                       the driver.

Copied from:

qapi/block-core.json:928:# @discard-nb-ok: The number of successful
discard operations performed by
qapi/block-core.json:931:# @discard-nb-failed: The number of failed
discard operations performed by
qapi/block-core.json:940:      'discard-nb-ok': 'uint64',
qapi/block-core.json:941:      'discard-nb-failed': 'uint64',

> 
> Using plural ("unaligned-accesses" and "aligned-accesses") makes it
> clear that the value is a count. It's also consistent with the existing
> "wr_operations" and "failed_operations" stats.

OK, I'll update.

Thanks for the review,

Phil.