[tor-relays] Raspberry Pi Relay Node Performance and future Plans on Documentation and more

[Gordon Morehouse]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

Nick Mathewson:
> Circuit creation happens within the Tor protocol.  How many
> circuit creation requests you get at once is a function of how much
> bandwidth you appear to have.  How many you can handle is a
> function of how fast your CPU is, and how fast your crypto
> implementation is.

Slow and slow, for the Raspberry Pi.  I have started gathering student
hand-optimized crypto routines from around the net that are written
from ARMv6, but that's a looooong ways away.

> You can decrease how much bandwidth you appear to have with 
> "MaxAdvertisedBandwidth", but you already knew that.

Yep.  I just don't understand why it's so spiky.

> One thing that you should try is seeing whether the latest 0.2.4.x 
> release does any better for you.  In particular, I'd recommend
> trying the just-released 0.2.4.16-rc, with openssl 1.0.1e, and make
> sure that openssl 1.0.1e was built with the
> -enable-ec_nistp_64_gcc_128 option if possible.  (I see you're
> already using 1.0.1e, but it doesn't appear to have been built with
> that option.)

Yeah, I just noticed this morning that because I'd installed the Pi a
few months ago before I upgraded to 0.2.4.x everywhere (figured I
might as well when I upgraded my bridges to obfs3), it's still on 0.2.3.x.

> Using 0.2.4.x should let Tor use a faster circuit extension
> handshake to clients that support it.  It will also have Tor use an
> improved algorithm for deciding how long is too long for a circuit
> queue. Instead of limiting the queue to a fixed number, it limits
> the size of the queue based on the expected time to clear it.

I'll try it in the next day or two.

> (Another thing to look at would be the output of ./src/test/bench
> in the 0.2.4.x package.)

And I'll try that and post it.

- -Gordon

-----BEGIN PGP SIGNATURE-----

iQEcBAEBCgAGBQJSCQ4oAAoJED/jpRoe7/ujw6IIAKMJZr+h+VLfoTd4VjKehsrF
qNNw3nstx82bAcaehKEFPSrvkIH2FRO+FqYR6ai+pWHTV8zZI593GA46Mb+9ElUU
Gpifg/D0oJtitsjwzB1MQ+MqNfqa7/13jQ45nm5J9ip51KqbyUwgwR4XAhFRxQ8H
J7Uv47SRqSd4sV0YQSC2rBOYFStLz0tYsN89L4ArC6mph83aNqpM0W2vopkRbO2R
xC8//NmWQ93wsqkRFHpc3jZVsTuURx3YmgiCF4mpn/me7X/o0j9bhP8ZOmWW/vfB
6kdGG7a0tBYcciQk7VWqNHsGMh+PEIJCPAOS+sbeeds+0ZN8BPbXSRwHj/0OQ8s=
=C2cg
-----END PGP SIGNATURE-----