Questions about setting up a new computer

Kyle kyle4jesus at gmail.com
Sun Jul 17 23:30:54 UTC 2016


The only problem with SSD is the limited life span of flash storage. 
SSD's can be read infinitely, but may only be written a relatively small 
number of times, making them very fast, but prone to failure. The best 
ways I have found to prolong the life of any flash storage is to disable 
filesystem journaling, which brings with it serious data corruption 
problems in case of a power failure, and to minimize log writes, for 
example by setting the log storage to volatile in 
/etc/systemd/journald.conf, which does indeed minimize writes, but will 
not allow reading a log after a reboot if you need to determine why 
something failed that forced a reboot or caused the kernel to freeze or 
reboot the system. Also, never under any circumstances create a 
permanent swap partition on SSD media, and use swapfiles only in cases 
where you are compiling something extremely large, which will not 
compile entirely in RAM, or if for any other reason you need a swapfile 
for a very very short time, which you will then disable and delete once 
it is no longer needed. With 8GB of RAM, you will likely not need to 
worry about this at all, but then just don't create any swapspace unless 
you find your OOM killer working overtime due to a running process that 
you will only need for a short time. Keep in mind that every write to 
your disk, especially to the same file, will shorten the life of your 
SSD, even if the internal wear leveling is very good. It's like rubbing 
the eraser on a sheet of paper over and over. Eventually you will start 
wearing holes in the paper, even if you are careful not to rub the same 
spot every time.

That said, I have had the same eMMC chip in both an Odroid XU4 and an 
Odroid C2 over the course of about 5 months, and I see no signs of wear 
thus far, so it's possible that in many cases, the usable life of flash 
storage has indeed improved enough to the point where minimizing writes 
to an SSD may cause it to perform much better for a much longer amount 
of time. Still, there is usually no sign of actual wear on any flash 
media until it is too late, and the filesystem is rendered read-only, so 
be very careful when using flash of any kind for your root filesystem. 
Even now, it would seem best to use flash to store things that will be 
written a very small number of times and read millions of times, mainly 
to make backups and store things like music, movies and documents that 
change little, and use a magnetic hard disk to do the write intensive 
stuff, such as swap, logs, databases, journaled filesystems, etc.
Sent while strollin'




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