Amit, * Amit Kapila (amit.kapil...@gmail.com) wrote: > On Wed, Mar 15, 2017 at 12:53 AM, Stephen Frost <sfr...@snowman.net> wrote: > > If that's the case then > > this does seem to at least be less of an issue, though I hope we put in > > appropriate comments about it. > > I think we have sufficient comments in code especially on top of > function _hash_alloc_buckets().
I don't see any comments regarding how we have to be sure to handle an out-of-space case properly in the middle of a file because we've made it sparse. I do see that mdwrite() should handle an out-of-disk-space case, though that just makes me wonder what's different here compared to normal relations that we don't have an issue with a sparse WAL'd hash index but we can't handle it if a normal relation is sparse. Additional comments here would be overkill if we think that the lower layers are already all set up to handle such a case properly and we don't have to do anything special, but I had understood that we didn't generally think that sparse files would just work. I'm certainly happy to be wrong there because, if that's the case, it'd be a great way to improve the problems we have returning large chunks of free space in the middle of a relation to the OS, but if there is a real concern here then we need to work out what it is and probably add comments or possibly add code to address whatever it is. Thanks! Stephen
signature.asc
Description: Digital signature