hot usb sticks

[Miroslav Lachman]

Julian H. Stacey wrote:
> Has anyone else noticed how hot USB sticks can get when used for backup ?
> &  also that IO errors occur after a while, which go away after a cold reboot.
>
> Not the whole stick, but the metal connector gets hot, so chip is
> hotter still.  Obviously one won't notice this on large plastic
> encassed sticks, but 2 main sicks I use are:
>   sandisk 2Gig metal case "vendor" "0x0781"; "product" "0x5151";
>   delock 8G miniature (~ 3mm of platic beyond plug)
> 	 "vendor" "0x05e3" "product" "0x0727"
>
> I usually notice this when I am updating (writing) a crypted (gbde)
> UFS file systems using port/net/rdist6 (which only rewrites updated files).
>
> Source data is 1,446,438 K bytes in 42,611 files so average
> size of 34 K.  But a lot of the files are really small, (~/.* config
> &  mail files etc, so as rdist will be updating each one sequentially,
> &  each will take a read + write cycle on a stick block,&  as many
> small files will probably map to the same stick block, thats
> some concentrated cycles.
>
> More stick detail at
> http://www.berklix.com/~jhs/src/bsd/fixes/FreeBSD/src/jhs/etc/devd/jhs.conf
>
> Quite often I have to reboot my target host that has a stick inserted,
> I believe regardless of OS version on USB target host
>
> Possibly there might be less heating when only reading (as read
> cycles are also quicker), but mainly I'm backing up, writing.
>
> I was thinking of making a heatsink to clamp to a USB socket on an
> extension cable, but before that I'll try hanging a USB extension cable
> adjacent to a case fan.

I have a few USB sticks, some of them are really old (and fast!), for 
example 512MB A-Data with 200x speed, or 8GB 133x. These fast sticks are 
almost cool. Some cheap modern sticks are hot even if used as read-only 
for booting ZFS backup server, where whole base system is on UFS USB 
stick monted read-only and all writes are on ZFS partitions of 4 HDDs. 
Even in this RO scenario, the hot stick died after about 2 years. Writes 
on it was made about 3 times a year because of system or ports updates.

So in my case: newer -> cheaper -> slower -> hotter = shorter life.

Miroslav Lachman