← Back to team overview

maria-developers team mailing list archive

Re: [Commits] 1cd9319: myisam/aria: don't mess with IO_CACHE::file


Hi Sergei,

thanks for explanations. So -1 -> new_file (my_repair()) is a problem while
old_file -> new_file (mi_repair_by_sort()/mi_repair_parallel()) is somewhat
acceptable. I was just confused by ma_repair_parallel() change, which seem
to do old_file -> new_file too.


On Wed, May 27, 2015 at 10:07:07PM +0200, Sergei Golubchik wrote:
> Hi, Sergey!
> On May 27, Sergey Vojtovich wrote:
> > Hi Sergei,
> > 
> > I'm lost now. In Aria you did change very similar code and kept 
> > init_io_cache(-1) while init_io_cache(info->dfile) was moved down
> > and replaced with init_io_cache(new_file). This sounds reasonable.
> > FWICS MyISAM has very same code.
> > 
> > Isn't "temp" in fact info->dfile and not -1?
> Ok, the original problem. init_io_cache(-1) means that IO_CACHE uses a
> temporary file as a backing store. That is, when in-memory buffer is
> full, IO_CACHE creates a temporary file to keep the data.
> MyISAM in a couple of places was creating IO_CACHE with
> init_io_cache(-1) and later was replacing IO_CACHE::file. That is,
> IO_CACHE was created as if it was a temporary storage, but later changed
> to use a real file. Which is not a good idea now, as I (in a later
> changeset) detect temporary IO_CACHE's in init_io_cache.
> So, I've fixed MyISAM/Aria not to access internal IO_CACHE fields and
> create IO_CACHE to have the correct file descriptior from the start.
> Regards,
> Sergei