Re: strange perf regression with data checksums

2025-05-09 Thread Aleksander Alekseev
Hi Tomas, > While running some benchmarks comparing 17 and 18, I ran into a simple > workload where 18 throughput drops by ~80%. After pulling my hair for a > couple hours I realized the change that triggered this is 04bec894a04c, > which set checksums on by default. Which is very bizarre, because

Re: strange perf regression with data checksums

2025-05-09 Thread Aleksander Alekseev
Hi, > > I'm not claiming that hint bits are necessarily the reason for the > > observed behavior but when something is off with presumably read-only > > queries this is the first reason that comes to mind. At least we > > should make sure hint bits are excluded from the equation. If memory > > ser

Re: strange perf regression with data checksums

2025-05-09 Thread Tomas Vondra
On 5/9/25 14:53, Aleksander Alekseev wrote: > Hi Tomas, > >> While running some benchmarks comparing 17 and 18, I ran into a simple >> workload where 18 throughput drops by ~80%. After pulling my hair for a >> couple hours I realized the change that triggered this is 04bec894a04c, >> which set che

strange perf regression with data checksums

2025-05-09 Thread Tomas Vondra
Hi, While running some benchmarks comparing 17 and 18, I ran into a simple workload where 18 throughput drops by ~80%. After pulling my hair for a couple hours I realized the change that triggered this is 04bec894a04c, which set checksums on by default. Which is very bizarre, because the workload