[CRIU] Issues dumping MySQL process

[Pavel Emelyanov]

On 04/02/2014 11:53 AM, Deyan Doychev wrote:
> 
> On 04/01/2014 08:03 PM, Pavel Emelyanov wrote:
>> On 04/01/2014 04:11 PM, Deyan Doychev wrote:
>>> Hi!
>>>
>>> When I try dumping a mysqld process (along with the mysqld_safe one) I
>>> get the following errors:
>>>
>>> Error (proc_parse.c:419): Can't handle non-regular mapping on 3487's map
>>> 140731902361600
>> Damn, this is vma start and should be %x :)
>>
>>> Error (cr-dump.c:1426): Collect mappings (pid: 3487) failed with -1
>>> Error (cr-dump.c:1855): Dumping FAILED.
>>>
>>> As far as I can see these are caused by these mappings:
>>>
>>> 7ffeb7588000-7ffeb758d000 rw-s 00000000 00:09 2016904                   
>>> /[aio] (deleted)
>>> 7ffeb758d000-7ffeb7592000 rw-s 00000000 00:09 2016903                   
>>> /[aio] (deleted)
>>> 7ffeb7592000-7ffeb7597000 rw-s 00000000 00:09 2016902                   
>>> /[aio] (deleted)
>> Wow... These are mappings created by sys_io_setup(). We have never met
>> any application using this before, looks like your mysql is brand new :)
> 
> It is actually a Percona server version 5.5.36-34.0.
> 
> I dug deeper into this and checked where Percona uses the io_setup syscall. 
> It is in the InnoDB//code since 2009 and is controlled by the innodb_use_native_aio config option.
> 
> Dumping a MySQL daemon started with the following my.cnf succeds:
> 
> [mysqld]
> innodb_use_native_aio = false
> 
> I will stick to using MySQL this way.

Cool! Thanks for the report, Deyan, we'll look into implementing aio support.

Thanks,
Pavel