Re: BUG #14231: logical replication wal sender process spins when using error traps in function

Andrew Gierth wrote:

> A quick scan of the code suggests that the worst case is when blocks are
> being freed in FIFO order, which seems quite plausible in this case, and
> the performance is potentially O(N^2).
>
> So I think this is primarily an artifact of doing so much retail
> palloc/pfree in a single memory context.

As I recall, this is the main reason Andres stuck the slab cache in
reorderbuffer.  Maybe it'd be worthwhile to implement a different
MemoryContext tailored to this use case, and remove the slab cache
stuff.

--
Álvaro Herrera                http://www.2ndQuadrant.com/
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