Re: Making the most of memory?

* Chris Browne:

>> A dedicated RAID controller with battery-backed cache of ssuficient
>> size and two mirrored disks should not perform that bad, and has the
>> advantage of easy availability.
>
> That won't provide as "souped up" performance as "WAL on SSD," and
> it's from technical people wishing for things that some of those
> things actually emerge...

For WAL (I/O which is mostly sequential), the proposed approach isn't
that bad. You can easily get more than 15,000 write transactions per
second, with a single thread. Good luck finding a SSD NAS with a
60 usec round-trip time. 8->

Something which directly speaks SATA or PCI might offer comparable
performance, but SSD alone isn't sufficient.

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Florian Weimer <fweimer(at)bfk(dot)de>
BFK edv-consulting GmbH http://www.bfk.de/
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