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From: Carlos Ferreira <carlosmf.pt@gmail.com>
Date: Tue, 30 Dec 2014 14:06:57 +0000
Message-ID: <CAJpYY6XmOnYX4bm=YyXr5hoiFLXhoEFXDa44Z_Fn1fHNj8G5_w@mail.gmail.com>
Subject: Regarding Netmap internal memory allocation.
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To Luigi and to whom may be able to help

Hello all.

Is it possible to reduce the size of the memory buffer allocated by the
netmap module?
I'm asking this because I was implementing some testing code, using NICs
and a Tap device in an OpenWRT VM with 64MB of RAM.
Because of the small RAM amount, the nm_open crashed when the program tried
to netmap the tap device, after I previously netmapped one NIC successfully.
After the crash, I bumped the VM RAM to 256MB and the test program ran
well, but not without me noticing that the VM RAM consumption was
 increased about 90 MB by netmap.

Resuming, I want to know if there is a way to reduce the memory buffer
allocation, without recompiling the netmap kernel module.

Thank you for the attention.

-- 

Carlos Miguel Ferreira
Researcher at Telecommunications Institute
Aveiro - Portugal
Work E-mail - cmf@av.it.pt
Skype & GTalk -> carlosmf.pt@gmail.com
LinkedIn -> http://www.linkedin.com/in/carlosmferreira