Web Hosting Talk : Web Hosting Main Forums : Programming Discussion : IIS Memory Leak

[jack2004]

Hi,
I run several sites on a dedicated server using Win2k & IIS. The sites use classic ASP and a few COM components called from ASP. My problem is that inetinfo.exe grows and grows in size (above 200MB) until it gets so big that it IIS freezes and I have to reboot my server to get it to work. These days I go through this reboot cycle at least once a week.

I installed a program called CacheBoost (www .systweak. com/ cacheboost/) yesterday and it seamed to work pretty well (getting inetinfo down from about 80MB to it 50MB, and setting it to do this optimization every hour), but now inetinfo has grown from it initial 50MB to 90MB and refuses to get any smaller.

Does anyone know what causes this and how I can fix it?

-Jack

[protecweb]

Generally it is due to bad code. You need to track down which site is causing the problem and then go through their ASP code to see if you can spot anything slack. There are several tools to help you with this but you might want to take a look at Filemon > http://www.sysinternals.com/ntw2k/source/filemon.shtml
This will give you more of an idea as to what specific files or .dlls are causing issues.
Other peeps here will prbably give you some other ideas as there are many tricks to use to find who the resource hog is.

[Burhan]

Sounds like a process that isn't being terminated properly. You can use system monitor to track what's doing what (but I'm sure there is a dedicated utitlity for IIS that does this).

Just to be safe, have you applied all the (now very frequent) patches for Windows?

[json]

I have more than 5 years of experience building big solutions with COM on IIS (4, 5 and 6), and everytime we have had leak issue, it has been bad code.

Remember to close objects (if a close method exists), and set the object to nothing.. close connection to databases, don't use the application or session object to store other objects in, etc etc...

regards,
J.

[jack2004]

Thanks people,
I have coded all the ASP myself and I am usually good about closing everything, but I am sure that I have forgot to do it in a few places so I will go through all my code and check that everything is being closed.

Thanks again!


-Jack

[edomaz]

If you can't fiqure out why your memory is leaking even after looking at the code you could setup the IIS Recycler if you have Windows 2000. Or if you have Windows 2003 you can simply setup Application Pool recycling

[jack2004]

Thanks for the tip about IIS Recycler. Have read all the documentation on MS's site, but I still don't quite understand what it does.

Does it:

a) Restart IIS with downtime for my websites?
b) Clean IIS without downtime for my websites?

Thanks!

-Jack

[sunpost]

it looks like IIS5Recycle will create downtime...you determine when that will occur by time, requests, memory, etc.


if it is not too many sites consider using High (Isolated) level for each web site...
http://msdn.microsoft.com/library/de...rver112299.asp

or if you have an idea of which site might contain the offending code, just switch that one to high. it will create a DDLHOST.EXE, then watch the process for memory leaks. this can help you discover which site is causing the problem.

i keep all my well behaved sites in the medium(pooled) setting and none in the low.

[nkad]

This may be of some help: http://www.15seconds.com/issue/020206.htm It basically talks about IIS optimization and performance w/ components

[monware]

I think it is time to switch to a Win2003 Server. ISS 6.0 is more secure and reliable.