Just an update with some new numbers, dan's changes
brought down the time for a full clone from my home
connection down to 5m48s (down from 27m39s previously)
well done dan!
--Ray
On 2022-06-17 3:45 p.m., Dan McGrath wrote:
Just a heads-up that Ray and I took a packet capture on both ends for me.
Thanks to his capture, I noticed that the SVN server host was not
sending TCP window scale or SACK options. Ultimately this turned out to be
due to that host using the PF firewall "synproxy" state option, which
apparently was causing the TCP header options to be removed, which limited
the window size to 64k.
I have corrected this change to match the www host, and we did observe
some improvements that were hidden from me before due to my and the studio
IPs special treatment that bypassed this feature.
While it should help, I also tuned a few sysctl settings for send and
receive buffers. In addition, I noticed that the SVN server is also not
sending gzip/deflate accept headers for the files. No doubt this is going
to be a factor. However, there was a note from 2016 from myself explaining
that Brecht asked for the SVN compression to be disabled due to some client
problems. So, this will require some research, perhaps next week.
Anyway, hopefully it helps a bit until I can review some more settings.
Enjoy your weekend everyone!
Dan
On Fri, Jun 17, 2022, 2:22 PM Ray Molenkamp via Bf-committers <
bf-committers@blender.org> wrote:
=8<==[Editors note]=8<==
I'll be honest I'm 100% convinced mailinator will ruin
the little formatting I have done, I put a copy of this
email on https://developer.blender.org/P3014.
=8<====8<====8<====8<==
How much as I like the sentiment of "lets move to git will it
solve all these problems" lets be honest here, git.blender.org <
http://git.blender.org>'s
speed is nothing to write home about either it may or may not be
as glitchy as svn, but it still wouldn't be fast.
from my 300mbit connection in western Canada
Receiving objects: 6% (135931/2078159), 33.34 MiB | 458.00 KiB/s
total time for a clone off git.blender.org <http://git.blender.org>
27m39s
Cloning off https://github.com/blender/blender.git however
total time for a clone off github.com <http://github.com> 1m 52s
Now amount of finger pointing to client settings will convince me
it's a client setting at this point, but I'll be honest, I am all
the way in western Canada and that could definitely be a factor.
sooooo, lets investigate!
Let’s spin up an AWS EC2 instance in London, I'd say that be close
enough to Amsterdam, and let’s rule out any other CPU or Bandwidth
related factors as well, I threw a few dollars at it and got a
cn5.18xlarge instance (72 CPU’s 192gb memory, 100gbit ethernet)
overkill to do a git/svn test? yes.. yes indeed
first to rule out the blender.org <http://blender.org> servers lets
grab a ubuntu iso
off an .nl mirror (
https://mirror.nl.datapacket.com/ubuntu-releases/22.04/ )
2022-06-17 17:13:21 (232 MB/s) - ‘ubuntu-22.04-desktop-amd64.iso’
saved [3654957056/3654957056]
all right bandwidth is NOT going to be an issue on this box!
On to blender stuff:
cloning from git.blender.org <http://git.blender.org> 2m32.895s
svn checkout of lib/win64_vc15 2m56.388s (iftop said 65Mbit peak
rate)
yowza!
All right, so in London, safe to say all is well
lets move closer to my location, us-east-2 Ohio (same instance type
and os)
grabbing ubuntu from that same mirror
2022-06-17 17:31:00 (29.5 MB/s) - ‘ubuntu-22.04-desktop-amd64.iso’
saved [3654957056/3654957056]
all right, that has lost quite a bit of steam, but it's
still nothing to sneeze at, just to be sure lets grab
an iso off the Princeton university mirror 120MB/s ok..
good enough...
onto cloning blender
Receiving objects: 5% (104235/2078173), 25.44 MiB | 692.00 KiB/s
well... that's not looking promising... lets wait it out
cloning from git.blender.org <http://git.blender.org> 17m23.449s
sadface... lets try svn next, i lost patience and did not let
it finish.. iftop reported a top RX of 5.59Mbit though..
To summarize:
Ubuntu iso from mirror.nl.datapacket.com <
http://mirror.nl.datapacket.com> (Speed taken from wget)
My home - western Canada - 1.3 MB/s
AWS - London - 232 MB/S
AWS - Ohio - 29.5 MB/s
Clone of git.blender.org <http://git.blender.org> (time taken from
linux time command)
My home - western Canada - 27m39
AWS - London - 2m32
AWS - Ohio - 17m23
SVN Clone: (peak RX bitrate taken from iftop)
My home - western Canada - 1.5 Mbit/s
AWS - London - 64 Mbit/s
AWS - Ohio - 5.59 Mbit/s
Think the only thing we really can conclude is
that being further from the server is leading
to an "unhappy" time for the developer. Given
the fact the EC2 instances were 100% identical
between London and Ohio, it's unlikely to be a
client configuration issue.
--Ray
On 2022-06-17 10:10 a.m., Dan McGrath via Bf-committers wrote:
> Hi,
>
> Really, I would need to see a capture from both sides to dig into
it. I
> need to see what is being sent, and what is received on each side.
There
> could be some weird firewall stuff happening that is causing
fragmentation
> or blocking TCP options, or window scaling issues, etc.
>
> As for the default settings for tortoisesvn, the connection stuff
I was
> referring to was about TCP/IP behaviour, rather than an application
> setting. Either way, I need to see what is actually happening. The
fact
> that I can pull 5-8MB/sec (~40mbit) from Canada and not have a
single
> interruption is telling. Granted, the host only has around 100 or
200mbit
> allocated, iirc. Multiply that by a few dozen people and you have
a problem.
>
> For a simpler test, maybe try a large svn check, perhaps some old
FreeBSD
> ports svn repo if you can find one, something also in .NL, and see
how it
> goes, just to help eliminate your PC/firewall. Worst case
scenario, you can
> also poke me in chat and we can try some server side and client
side
> captures.
>
> TBH though, 1gig uplink just isn't a whole lot to serve our user
base ;)
>
> On Fri, Jun 17, 2022 at 11:45 AM Tom M <letter...@gmail.com>
wrote:
>
>> On Fri, Jun 17, 2022 at 5:20 AM Dan McGrath <
danmcgrath...@gmail.com>
>> wrote:
>>> Hi Tom,
>>>
>>> Long time no see :)
>>>
>>> I did some tests from home and found that, aside from slow
speeds, I was
>> able to checkout at least 5 or 6 gig of the bf-blender repo
without error
>> or having to retransmit.
>>
>> Yeah, looks like I was mistaking really slow download of the
larger
>> (.7 GB) libraries as freezing. I was averaging about .3 MB/s. I
used
>> a different SVN client and saw that it was indeed downloading (the
>> sliksvn doesn't provide any feedback on files in progress, only
once a
>> file completes) - It was taking about 40 minutes for each of the
>> larger files. It did complete eventually after about 5 hours.
>>
>>> I took the liberty of packet capturing the stream from my PC's
POV, and
>> placed them in the ftp download area[1], if you care to take a
look.
>>> The gist is that I was able to get around 5MB/sec for at least
5G of the
>> checkout, before I cancelled it.
>> Interesting, I usually get up to 3 MB/s download here normally
from
>> other sources, but was typically getting .3 MB/s, with occasional
>> bursts of higher speed to a max of .8 MB/s when it wasn't
downloading
>> the large files.
>>
>>> Now, my IP is a bit of a special case, so I am wondering if you
are just
>> hitting the server so hard with http requests in separate
sockets, or
>> something extreme, that is causing the system to block you for a
period of
>> time. For comparison, my PC only had about 4 sockets open to the
server for
>> the transfer. I would be curious to know if you are doing
pipelining, or
>> sending each request in a separate connection.
>> Whatever the sliksvn and tortoisesvn defaults are, I'd assume
they are
>> setup for typical usage.
>>
>>> If you can, the next time it happens, see if you are unable to
visit
>> Phabricator or resume the svn checkout process. It may not be a
firewall
>> issue, but without seeing some packet captures, I wouldn't be
able to
>> really guess. Ideally, try to capture a few packets, until
failure. At the
>> very least, you will need to snap 20b+20b=40b for IP+TCP headers,
but I
>> would suggest a tad higher, maybe 64b.
>>> Cheers,
>>>
>>> Dan
>>>
>>> [1] - https://download.blender.org/ftp/dan/svn-checkout/
>>>
>>>
>>>
>>> On Thu, Jun 16, 2022 at 2:43 PM Tom M via Bf-committers <
>> bf-committers@blender.org> wrote:
>>>> When checking out the libraries from SVN following the
directions on
>>>>
>>>> https://wiki.blender.org/wiki/Building_Blender/Windows
>>>>
>>>> The svn checkout of the libraries fails with significant
frequency,
>>>>
>>>> if you google you might stumble across using make svnfix
>>>>
>>>>
https://www.mail-archive.com/bf-blender-cvs@blender.org/msg151996.html
>>>>
>>>> Even after using it, I'm still having to do Ctrl C, and then
make
>>>> svnfix repeatedly (it downloads some files, than randomly
freezes,
>>>> sometimes after 20-50 files, sometimes after 100's of files).
>>>>
>>>> Git doesn't seem to have any problems, though.
>>>>
>>>> So might we consider migrating the libs to git, rather than
using SVN?
>>>>
>>>> LetterRip
>>>> _______________________________________________
>>>> Bf-committers mailing list
>>>> Bf-committers@blender.org
>>>> List details, subscription details or unsubscribe:
>>>> https://lists.blender.org/mailman/listinfo/bf-committers
>>>
>>>
>>> --
>>> Cheers,
>>> Danny
>>>
>>> ----------------------------------------------------------
>>> Danny McGrath - danmcgrath...@gmail.com
>>> GPG key: EDF6 AFF5 2086 F93A 1F59 36A5 44B6 26F3 6968 71CA
>
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