Re: g->GCthreshold overflow, possible bug?

[Roberto Ierusalimschy <roberto@...>]

> Today I noticed some strange behavior in my lua application:
> My application disables lua autogc and manually calls
> lua_gc(LUA_GCSTEP) regularly. When memory usage exceeds 2G, each
> call to lua_gc(LUA_GCSTEP) becomes a full gc cycle (retval = 1).
> I managed to track down the cause of this problem to the following
> line in lgc.c:
> 
> #define setthreshold(g)  (g->GCthreshold = (g->estimate/100) * g->gcpause)
> 
> When g->estimate exceeds 2G and gcpause remains its default value
> 200, GCthreshold will overflow uint32 range.
> [...]
> 
> Is this a bug?

Yes.


> Is there any known solution for this?

Did you try to change the pause to 100, to avoid the overflow?

-- Roberto