Re: [HACKERS] SearchSysCacheTuple(Copy)

[Hiroshi Inoue]

Tom Lane wrote: > Hiroshi Inoue <[EMAIL PROTECTED]> writes: > > Isn't it practical to replace all susipicious Search > > SysCacheTuple() by SearchSysCacheTupleCopy() ? > > That would replace a rare failure condition by a not-at-all-rare > memory leak. I'm not sure there'd be a net gain in reliability :-( > A more serious objection to SearchSysCacheTupleCopy is that once the > tuple is copied out of the syscache, there isn't any mechanism to > detect whether it's still valid. If an SI message arrives for a > recently-copied tuple, we have no way to know if we have a problem > or not. > Is it more serious than doing the wrong thing silently ? Is it more serious than forcing database restart ? We couldn't handle SI messages immediately. Cache machanism couldn't gurantee the validty of tuples without some locking mechanism in the first place. Regards. Hiroshi Inoue