Re: [Testperf-general] Re: ExclusiveLock

> From: Doug McNaught [mailto:doug(at)mcnaught(dot)org]
>
> "Bort, Paul" <pbort(at)tmwsystems(dot)com> writes:
>
> > One other thought: How does static RAM compare to disk
> speed nowadays?
> > A 1Gb flash drive might be reasonable for the WAL if it
> can keep up.
>
> Flash RAM "wears out"; it's not suitable for a continuously-updated
> application like WAL.
>
> -Doug
>

But if it's even 2x faster than a disk, that might be worth wearing them
out. Given that they have published write count limits, one could reasonably
plan to replace the memory after half of that time and be comfortable with
the lifecycle. I saw somewhere that even with continuous writes on USB 2.0,
it would take about twelve years to exhaust the write life of a typical
flash drive. Even an order-of-magnitude increase in throughput beyond that
only calls for a new drive every year. (Or every six months if you're
paranoid. If you're that paranoid, you can mirror them, too.)

Whether USB 2.0 is fast enought for the WAL is a separate discussion.