Remix.run Logo
Deeg9rie9usi 13 hours ago

Once again phoronix shoot out an article without further researching nor letting the mail thread in question cool down. The follow up mails make clear that the issue is more or less a non-issue since the benchmark is wrong.

adrian_b 11 hours ago | parent [-]

The following up mails conclude that the regression happens only when huge pages are not used.

While using huge pages whenever possible is the right solution and this should be enough for PostgreSQL, perhaps there are applications that cannot use huge pages and which are affected by the regression.

So I do not think that it is right to just ignore what happened.

scottlamb 5 hours ago | parent | next [-]

> While using huge pages whenever possible is the right solution and this should be enough for PostgreSQL, perhaps there are applications that cannot use huge pages and which are affected by the regression.

It will be more interesting to talk about those applications if and when they are found. And I wouldn't assume the solutions are limited to reverting this change, starting to use the new spinlock time-slice extension mechanism, and enabling huge pages.

It sounds like using 4K pages with 100G of buffer cache was just the thing that made this spinlock's critical section become longer than PostgreSQL's developers had seen before. So when trying to apply the solution to some hypothetical other software that is suddenly benchmarking poorly, I'd generalize from "enable huge pages" to "look for other differences between your benchmark configuration and what the software's authors tested on".

justinclift 4 hours ago | parent [-]

> It will be more interesting to talk about those applications if and when they are found.

Redis recommend disabling hugepages: https://redis.io/docs/latest/operate/oss_and_stack/managemen...

---

Actually, looks like they changed the log warning to be more specific, as it's just the "always" setting which seems to cause Redis grief?

https://github.com/redis/redis/issues/3895

Deeg9rie9usi 11 hours ago | parent | prev [-]

I agree with you. The lurid headlines of phoronix.com just annoy me...