-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 07/04/2015 06:19 PM, teor wrote:
make test-network is dominated by the 25 second delay waiting for the
Tor test network to bootstrap. So it's not going to help much.
I'm working on a chutney branch to measure bandwidth on "chutney
verify", but it doesn't have any command-line arguments yet (it's all constants in the code). I'll see if I can pull it into shape today.
Awesome I'm excited to try it out :D
Even with these bandwidth measurement changes, there's something else
to think about:
chutney will measure the combined throughput of 4-5 tor instances, and
4n - 5n cpuworker threads, where n is the number of cores on your machine. But this isn't the performance you're interested in for multithreaded crypto changes - you want to know how a single instance + n cpuworker threads performs. (A chutney test network is far *more* parallel than a typical tor relay.)
To get an accurate benchmark, you could run one tor instance per
machine, or, at the very least, run the client on a slow machine, and everything else on a fast machine, so that the client's multithreaded crypto is the limiting factor. But this seems like a lot of work, and I'm not sure how much accuracy you'll gain.
As a first step, you could minimise the number of tor instances, which
might make multithreading improvements easier to measure.
You'll find the basic-min network helpful for this: ./src/test/test-network.sh --flavour basic-min
Then check if you're using ~100% of all cores when you push large amounts (100MB+) of data through the network using #14175 (when it's done!) If you're not using 100%, then you'll be able to see any multithreaded improvements when you run the test again. If you are seeing 100% usage already, get more cores or more machines, and re-run the tests.
Let me know how you go with this. I too was thinking of how I would set up the test environment and this is probably more than I could have come up with in days! I'm all ready to check the cpu usage when you pump out the update.
You could also modify tor to use single-hop connections, then measure single-hop bandwidth, by making a 1-hop connection and pushing data through it. There won't be as much client crypto as the 3 or 4-hop scenario; and you'll still have the client and destination on the one machine, unlike the single relay real-world scenario. But it could be closer to real-world multithreaded performance, as you'll only be measuring 2n threads. (Ideally, you want to measure n threads.)
You must *never* use a tor binary built like this on the public tor network, as it has no anonymity. To make tor use 1-hop circuits for everything, change DEFAULT_ROUTE_LEN to 1 in or.h End dire warning about loss of anonymity.
Of course, 1-hop circuits might hide some subtle multithreading bugs, as there's less crypto happening overall. So please test the correctness of your code with DEFAULT_ROUTE_LEN 3 as well.
Done. I changed it to start with 1 and I will try 3 as well. If I shouldn't test this out on the public tor network, should I set up everything locally?
Give me 8 hours or so to work on #14175, I'll try and get it into a
usable state.
Tim
Dude, thanks a bunch for you help. I'm really excited to start :D I'm going to read through the initial design and the code to see what functions/structures/constants/etc. need to be changed. Let me know when you release #14175 and I'll be happy to be the test guinea pig =-) - - Cory -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJVmWdxAAoJEB7DuCIJauCgT28P/R1WliIB8P/3tCCPuSLE1oqX vheyu1ZaPPfYOZqemo5xvScyuoPQjASmlM6EG20IQddSrLdz3MU/eUDD604X/tmY r4/LvrWrHek+ER3kCFYvKvYCLO94pY6Sr5zha01iZHw0Vibvypp8lFQR4HOnjvGt LD0LOHJXwotFcHmHfdElHT3VozFhHPHqrTQlgI8ziFl+i54XPb8yuqRbT0glwX/r WztAjiFzuMybnA18IYFRmruLk2bb9ZgQOBGmonvWEi/FVdxkuiXc6b+UyC1q9IiG 4hdDVuwVvwa4iDJ8fWm1rGd81mMlIU6FuV77UOUZYg8/4EHFfFzzVynm0V1QhXzr /UKhTk/3alqcydDZ3rmeX0wsHpI9RKgrwxSXFTuFm+iydjZRcbeXS9ftv88jykMW RJ7qwmRfib0e1U+Uk3yXHHnb7k1Qt1kHxG5rFlFivsXSE06rVfq2visHlLJopAxJ 0bZ93d37tDN71yi8lBmko4mcmO4iKbTjAiw42h2Nj0iYvaM8FBrAz5i65QrlgBa8 LOTjEcxgFxeglIvInmnlf3muJvKrEYH9ikF2f6Wd1ggIqBzKxPxfyhC/0EPPJ9to PYdqHH2VzwimhwXergEec6EWnTTyYE66iDHszzLV8KZNkFa+7nFq3VNK6KneIwTD uklR2RCxwPjUgNaOwbdF =z2cK -----END PGP SIGNATURE-----