maria-developers team mailing list archive

[Sergey Vojtovich <svoj@xxxxxxxxxxx>]

Hi Alexey,

Just soem thought from my side...

> +const char *ap_get_database(MYSQL_THD thd)
> +{
> +  if (!thd)
> +    return "";
> +
> +  return thd->db;
> +}
I think this should be benchmarked with perf. Things like this ain't good
performance wise (we already fixed a bunch of those). That is when function call
convention is more expensive than payload. Especially if you call this many
times per query.

Check for thd != NULL is not performance wise either (because payload is really
small). I believe that thd must be set in all cases: auditing something that
doesn't have context sounds a bit strange.

> +  uint audit_event_code;
> +  const void *audit_event_data;
Why? Just to avoid passing this as an argument? Though these are normally just
12 bytes, (FWICS) you only need them for a very short duration. All other time
it's just waste of memory. It's not a problem alone, but THD is already way too
overloaded by things like this. This point was originally risen by Vicentiu
back in Amsterdam.

In a nutshell, performance wise it is best if there's just one function call per
event.

Regards,
Sergey


On Sun, Oct 23, 2016 at 01:16:07PM +0400, Alexey Botchkov wrote:
> Hi, Sergei.
> 
> I'd like to draw your attention to this old issue:
> https://jira.mariadb.org/browse/MDEV-7389
> 
> The idea was to make a bigger thing - to modify the plugin API
> so it is easier to use and let user to do more. Particularly to
> notify warnings to the audit plugins for this 7389 task.
> That was done with this task: https://jira.mariadb.org/browse/MDEV-5313
> 
> Just to refresh our memory:
> I proposed to get rid off the API versions and version-dependent
> memory structures that are used to transfer data to and from the plugin.
> All we need to do is adding new 'audit_plugin_service'. Which is
> just the normal service that offer methods to the auditing plugin to
> send commands to the server and get the server data. You can look at the
> patch http://lists.askmonty.org/pipermail/commits/2016-February/009025.html
> 
> So, Serg, do you have anything to say on that subject?
> 
> Best regards.
> HF
> 
> 
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