[clug] SSD drives and lots of writes

[Kim Holburn]

I like my Macbook air.  I like it because it's light, fast, stable and runs unix.  I hate that Apple has soldered the memory to the board so you can't change it and I'm not so happy the direction they're going with their GUI.  But even if it has limited memory, it has an SSD drive which means you can run lots of applications and it pages very fast because of the SSD.  

This gave me the idea of running my linux system at home with an SSD system disk.  SSD disks big enough to hold a system are not that expensive anymore.  

I mentioned it to someone at my work and they said: don't put /var/log on the SSD because it will shorten the life with all that writing.  Oh I thought yes, SSDs have a limited number of writes, everyone knows that, but is it true?  And is it true that file systems really do write that often or do they cache the writes and write in a big bunch?  (Even if atime is on.)  I noticed that the latest ubuntu has a default of mounting partitions with relatime which is similar to noatime.  Good.  If /var/log was bad then swap would be bad too.  

So I thought, perhaps I could get another smaller SSD drive, say 20GB or 30GB for swap (and maybe /var/log).  I could flog it with writes while my system disk was mostly just reads and would last a long time.  But is this all true?  What are your thoughts about whether modern SSD drives have their life shortened by lots of writes?


Kim

PS: my system boots tremendously fast from the SSD.

-- 
Kim Holburn
IT Network & Security Consultant
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