Svn.exe for windows very slow on high ping connections

[Charles Alexander <ch...@gmail.com>]

I'm using svn.exe (1.9.5), connecting through svn+ssh using Plink.

For a nearby DigitalOcean server (in New York, 60ms ping), I get checkouts
and commits at hundreds of KB/s.  But I am collaborating with someone from
Australia and he was getting really slow checkouts and commits to the
server.

After lots of troubleshooting, I couldn't find anything that would speed it
up for him.  I tried making a digital ocean server in Singapore to see if
it would be fast for him, and still be fast for me.  While it is faster for
him, I ended up seeing the same exact poor speeds he was seeing.

The Singapore test server has a 280ms ping for me.  My checkouts go at
almost exactly 60KB/s.

However, if I checkout from a linux VM on my same machine, through the same
internet, using the linux svn client, I get hundreds of KB/s even to
Singapore.

Worried it might be an issue with Plink/PuTTY, I tried copying a large file
with PuTTY's pscp.exe, and it goes at around 3400 KB/s, without compression.


Anyone have any ideas on what could be causing the slow down?  A checkout
of the same exact repository from the New York server goes around ten times
faster.  And a checkout from a linux VM on the same desktop I am running
svn.exe from went about the same, even to the Singapore server. Everything
also goes slow when I use TortoiseSVN and not the commandline.

Let me know if there is any more information I can provide to help track
this down.

Thanks,
Charles Alexander

Re: Svn.exe for windows very slow on high ping connections

[Charles Alexander <ch...@gmail.com>]

I think I found the solution:

https://marci.blogs.balabit.com/2009/11/putty-performance/

PuTTY has a 16KB receive window unless you have a one way connection, then
it gets a 2MB one (and that's why I was able to run pscp.exe [PuTTY scp] at
full speed).

So the solution is to patch PuTTY to use a larger window on two-way
connections.  With 250ms ping to Singapore, the receive window would only
get emptied four times a second, resulting in the ~60KB/s I was stuck with.

On Jan 13, 2017 10:56 PM, "Charles Alexander" <ch...@gmail.com>
wrote:

> One other thing: I also tried with and without Nagle's algorithm in the
> PuTTY profile.
>
> On Fri, Jan 13, 2017 at 10:49 PM, Charles Alexander <
> charlesalexander@gmail.com> wrote:
>
>> I'm using svn.exe (1.9.5), connecting through svn+ssh using Plink.
>>
>> For a nearby DigitalOcean server (in New York, 60ms ping), I get
>> checkouts and commits at hundreds of KB/s.  But I am collaborating with
>> someone from Australia and he was getting really slow checkouts and commits
>> to the server.
>>
>> After lots of troubleshooting, I couldn't find anything that would speed
>> it up for him.  I tried making a digital ocean server in Singapore to see
>> if it would be fast for him, and still be fast for me.  While it is faster
>> for him, I ended up seeing the same exact poor speeds he was seeing.
>>
>> The Singapore test server has a 280ms ping for me.  My checkouts go at
>> almost exactly 60KB/s.
>>
>> However, if I checkout from a linux VM on my same machine, through the
>> same internet, using the linux svn client, I get hundreds of KB/s even to
>> Singapore.
>>
>> Worried it might be an issue with Plink/PuTTY, I tried copying a large
>> file with PuTTY's pscp.exe, and it goes at around 3400 KB/s, without
>> compression.
>>
>>
>> Anyone have any ideas on what could be causing the slow down?  A checkout
>> of the same exact repository from the New York server goes around ten times
>> faster.  And a checkout from a linux VM on the same desktop I am running
>> svn.exe from went about the same, even to the Singapore server. Everything
>> also goes slow when I use TortoiseSVN and not the commandline.
>>
>> Let me know if there is any more information I can provide to help track
>> this down.
>>
>> Thanks,
>> Charles Alexander
>>
>>
>

Re: Svn.exe for windows very slow on high ping connections

[Charles Alexander <ch...@gmail.com>]

One other thing: I also tried with and without Nagle's algorithm in the
PuTTY profile.

On Fri, Jan 13, 2017 at 10:49 PM, Charles Alexander <
charlesalexander@gmail.com> wrote:

> I'm using svn.exe (1.9.5), connecting through svn+ssh using Plink.
>
> For a nearby DigitalOcean server (in New York, 60ms ping), I get checkouts
> and commits at hundreds of KB/s.  But I am collaborating with someone from
> Australia and he was getting really slow checkouts and commits to the
> server.
>
> After lots of troubleshooting, I couldn't find anything that would speed
> it up for him.  I tried making a digital ocean server in Singapore to see
> if it would be fast for him, and still be fast for me.  While it is faster
> for him, I ended up seeing the same exact poor speeds he was seeing.
>
> The Singapore test server has a 280ms ping for me.  My checkouts go at
> almost exactly 60KB/s.
>
> However, if I checkout from a linux VM on my same machine, through the
> same internet, using the linux svn client, I get hundreds of KB/s even to
> Singapore.
>
> Worried it might be an issue with Plink/PuTTY, I tried copying a large
> file with PuTTY's pscp.exe, and it goes at around 3400 KB/s, without
> compression.
>
>
> Anyone have any ideas on what could be causing the slow down?  A checkout
> of the same exact repository from the New York server goes around ten times
> faster.  And a checkout from a linux VM on the same desktop I am running
> svn.exe from went about the same, even to the Singapore server. Everything
> also goes slow when I use TortoiseSVN and not the commandline.
>
> Let me know if there is any more information I can provide to help track
> this down.
>
> Thanks,
> Charles Alexander
>
>