Repeated "system lacked sufficient buffer space" messages

[crunchyfrog555]

Have been using uTorrent for months now, and over the last couple of months I've been getting this problem.

When I leave my PC on for some time (usually overnight) and it downloads between 1.5 and 1.8 Gigabytes, I get the "operation on a socket could not be performed because the system lacked sufficient buffer space...". Naturally, the only way to cure this is to reboot the PC - closing and reopening uTorrent has no effect.

Checked your FAQ pages and glanced through your forums and tried every recommendation I could find. Namely:

Patching XP so it allows ports up to 65535.

Patching XP with the other patch (can't remember what it's called), after every time I get a XP update.

I don't use Norton at all, and the only similar software I have installed is Sophos anti-virus software (which is only active when I manually scan for viruses) and whatever automated systems may be in place within current version of XP.

Also, this problem has appeared whilst being with 3 different ISPs (I'm currently with Lixxus).

My hardware is a 1.7GHz eMachines affair with 1024Mb RAM, 1 x 40Gb hard drive and 1 x 250Gb external USB hard drive, 1 x NEC DVD writer and 1 x Samsung DVD reader.

That's about all I can think of. IF you've any other information, please email me.

[Ultima]

Er... XP doesn't need a patch to allow "ports up to 65535" -- that's already "built-in" due to the very nature of TCP/IP networking standards ;o

Can you provide us with a list of processes running on your computer the next time you see the problem? If you're not sure how to do that, get Process Explorer from sysinternals.com, File > Save, then copy and paste the process list in the .txt file that you save from there.

[crunchyfrog555]

OK, here we go. Processes open when the problem happens:

GoogleToolbarNotifier.exe

taskmgr.exe

hposts08.exe

hpoevm08.exe

hpotdd01.exe

hpohmr08.exe

ALMon.exe

ctfmon.exe

MSASCui.exe

alg.exe

DslStat.exe

wscntfy.exe

wdfmgr.exe

svchost.exe (x6)

StarWindService.exe

ALsvc.exe

SAVAdminService.exe

spoolsv.exe

iTunesHelper.exe

explorer.exe

SavService.exe

MsMpEng.exe

lsass.exe

services.exe

winlogon.exe

csrss.exe

smss.exe

jusched.exe

iPodService.exe

System

System Idle Process

And just so you know, the CPU's running at about 4-5% whilst this happens.

One note regarding the patch of ports to 65535 - I guessed that XP used that many, but I was just following the recommendations on your FAQ pages.

[Ultima]

Sophos AntiVirus is something I'd keep my eyes on as a possible suspect... Additionally, maybe dslstat.exe is incompatible? I'm not sure here, as you don't appear to be running any of the "usual" suspect processes =\

[crunchyfrog555]

I'll try a few things out then, and see where it gets me.

Anyhow, I'd just like to say thank you very, very much for your help and the promptness of the replies - I really do appreciate it.

[Sium]

This has been happening to me too however i've also noticed that all other internet programs stop working aswell, all saying there are no free sockets.

It seems that the new uTorrent is allocating new sockets for each connection but isn't freeing sockets when the connection is no longer used. Over time the sockets just get used up until uTorrent is closed and the sockets released by the OS.

It's only happened since 1.6.1 but does happen everytime which is why i waited, i assumed it was so blatent there would be a newer version out by now with a fix.

System: WinXP SP2, AMD 4200+, 2gig ram, etc...

[Firon]

This usually happens when you set your net.max_halfopen to a very high value and don't patch tcpip.sys (or your patch got reverted).

[Sium]

Ok, i changed my halfopen from 8 to 4 and patched my tcpip.sys so I'll check it over the next few days to see if it's sorted.

Thanks for the advice

[paulb104]

I have a similar issue, using 1.6.1.

I let utorrent start downloading at night before bed, and in the morning the download is a zero. My email program gives an error message "no buffer space available" message. Firefox is useless as well - pages do not come in.

I have two computers going through one router into the cable modem. Rebooting the machine with the download doesn't fix the issue. Rebooting both machines at the same time doesn't fix the issue. I have to turn off the modem, the router, and both computers to fix the issue.

My net.max_halfopen is set at 8.

I didn't have any issues with the previous version (which I no longer have).

Sometimes the buffers get full within an hour of starting utorrent, which means that hours go by without any network activity. My Weatherbug program always shows the time of its last connection so I know when the connection failed.

Any useful advice will be truly appreciated.

Paul

[DreadWingKnight]

Weatherbug.

Why does that sound like spyware to me?

[Sium]

My uTorrent has been running constantly since the post and its still going fine, normally it'll freeze up after only a couple of hours.

So it seems to be sorted

[paulb104]

You had said you changed "halfopen from 8 to 4 and patched my tcpip.sys".

What do you mean by "patched my tcpip.sys"? How does one know if it needs to be patched, and where does the patch come from?

My computer has eight files named tcpip.sys. Here they are, in chronological order:

C:\WINDOWS\ServicePackFiles\i386 08/04/2004 02:14 AM 359,040

C:\WINDOWS\$hf_mig$\KB893066\SP2QFE 05/25/2005 03:07 PM 359,936

C:\WINDOWS\$NtUninstallKB913446$ 05/25/2005 03:04 PM 359,808

C:\WINDOWS\$hf_mig$\KB913446\SP2QFE 01/13/2006 01:07 PM 360,448

C:\WINDOWS\$NtUninstallKB917953$ 01/12/2006 10:28 PM 359,808

C:\WINDOWS\$hf_mig$\KB917953\SP2QFE 04/20/2006 08:18 AM 360,576

C:\WINDOWS\system32\dllcache 04/20/2006 07:51 AM 359,808

C:\WINDOWS\system32\drivers 04/20/2006 07:51 AM 359,808

[Firon]

http://lvllord.de/

[paulb104]

So I changed net.max_halfopen to 4, and I went to http://lvllord.de and downloaded EventID 4226 Patcher Version 2.23d.

I ran the program, changing the maximum concurrent half-open connections to 50, as it asked. I started utorrent which downloaded all night, and it's still going.

After Googling 'maximum concurrent half-open connections' I came across this page: http://www.p2pforums.com/viewtopic.php?t=10525. In that thread there is a question, "can i set it over 50? will it be faster?" to which the reply is "Maybe, but it will also be less secure."

My own questions:

If tcpip.sys is set to 50, and utorrent is set to 4, what exactly does that mean?

One of the posters in that thread, from late 2005, has this in their tag:

Sick of being banned from private trackers with BitComet?

Try: http://www.utorrent.com

Only a 115 KB EXE! with Azureus like GUI.

I wish I'd seen that then - I've gone through a number of BT clients before I found utorrent....

[DreadWingKnight]

net.max_halfopen controls the number of connections that uTorrent is ATTEMPTING to make.

Think of it like phonecalls. Half-open connections are like phonecalls that are dialing or dialed and ringing.

Increasing the halfopen limit doesn't affect speeds that much, and only really has a measurable effect on the initial connect phase on firewalled clients. Once you get connectable, you don't see any real difference, since you get a lot of incoming connections that prevent you from needing to use your halfopen outbound connections.