Re: Reduce pinning in btree indexes

>>>>> "Kyotaro" == Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp> writes:
Kyotaro> Just a reminder, but I am not the author of this patch:)

Yes, I understand that.
Kyotaro> Mmm? The patch bt-nopin-v1.patch seems not contain the changeKyotaro> for ExecSupportMarkRestore and the very
simplefunction remainKyotaro> looking to return true for T_Index(Only)Scan after the patchKyotaro> applied.
 
>> Right. I'm suggesting you change that, in order to determine what>> performance cost, if any, would result from
abandoningthe idea of>> doing mark/restore entirely.
 
Kyotaro> I understand that you'd like to see the net drag ofKyotaro> performance by the memcpy(), right?

No.

What I am suggesting is this: if mark/restore is a performance issue,
then it would be useful to know how much gain we're getting (if any)
from supporting it _at all_.

Let me try and explain it another way. If you change
ExecSupportMarkRestore to return false for index scans, then
btmarkpos/btrestorepos will no longer be called. What is the performance
of this case compared to the original and patched versions?

-- 
Andrew (irc:RhodiumToad)