bootarg.init.low_mem

[papadopoulosa]

I'm trying to find out if I need to change this setting.  I've provided 4GB's of RAM for my vSIM's, but I keep seeing this setting and wonder if it restricts performance of the vSIM since it is only allocating 512MB for the FreeBSD portion.

Are there any other performance improvements I can make by changing any of the configuration options?

[shatfield]

If you gave your vsim 4gb, you can set that value to 760 or just unset it.  It restricts the ram available to the bsd environment to keep ontap functional when its only got the default 1600mb to work with.

[papadopoulosa]

So is it best to leave it as is and provide CDOT the memory, or will it help to unset  it?

Thanks for the answer  Sean.

Tas

[shatfield · Accepted solution]

Hard to say, really.

Leaving it trimmed to 512 may give ontap more ram for caching which should help performance

Leaving it trimmed to 512 may cause additional swap activity which should hurt performance

All the jumbo 4gb vSIMs I've seen have it set to 760.

[papadopoulosa]

Thanks Sean.  That works for me.

[papadopoulosa]

Sean:

I changed the value, and it had the effect of causing the filer to panic on bootup.  I changed it back to 512.

[shatfield]

I couldn't get mine to panic, but its CDOT8.2.2RC1.  What mode/version are you running?

[papadopoulosa]

CDOT 8.2.1