Mesa's Shader Cache Will Now Occupy Less Disk Space

[phoronix]

Phoronix: Mesa's Shader Cache Will Now Occupy Less Disk Space

Mesa previously had a hard-coded limit to not take up more than 10% of your HDD/SSD storage, but now that limit has been halved...

http://www.phoronix.com/scan.php?page=news_item&px=Mesa-5-Cache-Limit

[GI_Jack]

Am I the only one that things that disk caching is a really bad idea. Or mabey its for people still using HDDs with very limited drive bandwith, or that hard drives, and especially solid state drives have limited lives and this might thrash a disk or two?

[M@GOid]

Am I the only one that things that disk caching is a really bad idea. Or mabey its for people still using HDDs with very limited drive bandwith, or that hard drives, and especially solid state drives have limited lives and this might thrash a disk or two?

SSDs will not end their lives because games wrote a few MB per day. People seems to get attached to this myth that SSDs will die if you let any application write constantly on them. Get over it, the life span is enormous and to kill one it take years writing several GB daily. So no, you will not grenade your SSD just using it like a HDD.

[mibo]

Am I the only one that things that disk caching is a really bad idea. Or mabey its for people still using HDDs with very limited drive bandwith, or that hard drives, and especially solid state drives have limited lives and this might thrash a disk or two?

You are the only one.
The fear that ssds do wear out quickly is an old tale that never[*] really was a problem.
Nowadays, swap and cache files are saved to ssd.[*] of course one can write the ssd flash memory to death. But, under normal use that just doesn't happen.

[humbug]

Am I the only one that things that disk caching is a really bad idea. Or mabey its for people still using HDDs with very limited drive bandwith, or that hard drives, and especially solid state drives have limited lives and this might thrash a disk or two?

I would want my cache on the SSD for performance reasons. SSD lifespans are very long, more reliable than hard drives.

read below the extent techreport had to go to wear out flash

http://techreport.com/review/27909/the-ssd-endurance-experiment-theyre-all-dead

and imagine doing that to a HDD

[cj.wijtmans]

we really need a file system that works similar to redis. heck it would render redis obsolete as you could make a filesystem blob on tmpfs. Would be amazing for my cached files on disk on server.

[schmidtbag]

My personal paranoia of SSD lifespan is linked to things like paging/swap files. Some OSes (*cough* Windows) will "unnecessarily" (quoted because it is arguably good) write to an SSD despite there being several GB of free RAM. Aside from that, I'm confident my SSDs will last me a long time, and there's nothing to worry about for these shader caches.

However, I am opposed to the idea of unnecessary wear. If the performance improvement of a shader cache is mostly negligible, I'd rather spare my SSD the write cycles.

[log0]

It seems some people are confused about how such caches work. It does not constantly write shaders, but only when it hits new ones or invalidates older entries. This means few writes and many reads.

[Nille_kungen]

The very first SSD had those problems but now it's a thing from the past that many think still is present.
I do think 5% is very much, if i have an 3TB hdd then 5% is to much and it should have an max limit rather the %.
I haven't played with shader cache and don't know how much it will use and how fast, i only thought 5% can be a very vast amount och space.

[M@yeulC]

Two ideas come to my mind. How about:

• Make the limit a percentage of the free space
• Cleaning up older driver's entries (possibly checking the file creation date)

Is there any downside I overlooked?