Re: PostgreSQL on S3-backed Block Storage with Near-Local Performance

> This then begs the obvious question of how fast is this with
> synchronous_commit = on?

Probably not awful, especially with commit_delay.

I'll try that and report back.

Best,
Pierre

On Fri, Jul 25, 2025, at 00:03, Jeff Ross wrote:
> On 7/24/25 13:50, Pierre Barre wrote:
>
>> It’s not “safe” or “unsafe”, there’s mountains of valid workloads which don’t require synchronous_commit. Synchronous_commit don’t make your system automatically safe either, and if that’s a requirement, there’s many workarounds, as you suggested, it certainly doesn’t make the setup useless.
>>
>> Best,
>> Pierre
>>
>> On Thu, Jul 24, 2025, at 21:44, Nico Williams wrote:
>>> On Fri, Jul 18, 2025 at 12:57:39PM +0200, Pierre Barre wrote:
>>>> - Postgres configured accordingly memory-wise as well as with
>>>> synchronous_commit = off, wal_init_zero = off and wal_recycle = off.
>>> Bingo. That's why it's fast (synchronous_commit = off). It's also why
>>> it's not safe _unless_ you have a local, fast, persistent ZIL device
>>> (which I assume you don't).
>>>
>>> Nico
>>> --
> This then begs the obvious question of how fast is this with
> synchronous_commit = on?