Re: [PATCH v2] Introduce the end_syncfs option

Damien Le Moal
2026-01-27T02:18:50Z

On 1/27/26 11:15, Vincent Fu wrote:
> On Mon, Jan 26, 2026 at 9:05 PM Damien Le Moal <dlemoal@kernel.org> wrote:
>>
>> On 1/27/26 10:01, Vincent Fu wrote:
>>> On Mon, Jan 26, 2026 at 1:22 AM Damien Le Moal <dlemoal@kernel.org> wrote:
>>>>
>>> <snip>
>>>> }
>>>> +
>>>> + if (td->o.end_syncfs) {
>>>> + td_set_runstate(td, TD_FSYNCING);
>>>> +
>>>> + for_each_file(td, f, i) {
>>>> + if (fio_file_syncfs(td, f))
>>>> + log_err("fio: end_syncfs failed\n");
>>>> + break;
>>>
>>> This seems like it will break out of the loop after syncfs-ing the first file.
>>> Is this intentional or should fio break only if there is an error?
>>
>> It is intentional and it is the entire point of this patch: doing syncfs for the
>> first file will sync the entire FS, so all the other files will be sync-ed as
>> well. We thus avoid the entire loop on all files which is extremely slow when
>> running with a large number of files. We only need to do syncfs() once for the
>> first file. Ideally, we should do it for the directory specified for the files,
>> but that is a little more involved as a change.
>
> Ok thank you for clarifying.
> Please emphasize in the documentation that this feature assumes that
> all files will reside on the same file system.

OK. Will do in v3.

>
> Vincent

--
Damien Le Moal
Western Digital Research