On 2020-08-27 23:50, Chris Murphy wrote:

DATA/COMPR is the actual compression ratio
DATA/TOTAL is the effective compression ratio, which includes a bit of
overhead and fragmentation of the zram device (the difference between
COMPR and TOTAL)

Thanks.

I suspect zram-fraction=0.75 also would have succeeded. But it's fine
to leave it set to 1.0. And as these are VMs mainly for testing, you
could even set it to 2.0, and see if you run into issues.

I did previously run with 0.75 and while it ran longer it did crash before completion.

I'll give 2.0 a try in the coming days. If anything interesting occurs I'll post back.

The other reason for caps for systems with more memory, is the zram
device does have a bit of overhead. It's cheap and worth it if the
zram device is being utilized. But it's a waste, however small, if the
zram device isn't being used. In your case, it'd be used so you could
test with a fraction anywhere between 0.5 and 2.0. If you don't want
to test it, 1.0 is pretty safe.

OK.

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