Re: [gentoo-user] Re: [Gentoo-User] emerge --sync likely to kill SSD?

[Peter Humphrey <peter@prh.myzen.co.uk>]

On Friday 20 June 2014 19:48:14 Kai Krakow wrote:
> microcai <microcai@fedoraproject.org> schrieb:
> > rsync is doing bunch of  4k ramdon IO when updateing portage tree,
> > that will kill SSDs with much higher Write Amplification Factror.
> > 
> > I have a 2year old SSDs that have reported Write Amplification Factor
> > of 26. I think the only reason is that I put portage tree on this SSD
> > to speed it up.
> 
> Use a file system that turns random writes into sequential writes, like the
> pretty newcomer f2fs. You could try using it for your rootfs but currently I
> suggest just creating a separate partition for it and either mount it as
> /usr/portage or symlink that dir into this directory (that way you could
> use it for other purposes, too, that generate random short writes, like log
> files).

Well, there's a surprise! Thanks for mentioning f2fs. I've just converted my 
Atom box's seven partitions to it, recompiled the kernel to include it, 
changed the fstab entries and rebooted. It just worked.

--->8

> I'd also suggest not to use the discard mount options and instead create a
> cronjob that runs fstrim on the SSD devices. But YMMV.

I found that fstrim can't work on f2fs file systems. I don't know whether 
discard works yet.

Thanks again.

-- 
Regards
Peter