I have noticed this for a while now. It would slowly grow and grow and grow, even if I have 100 sessions max to keep. I may have noticed a few times when it's grown past a gigabyte in memory, to start growing more exponentially, as much as two megabytes per "refresh" in browser window. However, the real problem is that it also does it when there's filters turned on. To my understanding, filters should prevent traffic that doesn't pass them from being stored anywhere. The main reason why I have noticed it, is because I work with an external API to monitor all the calls towards them (ie if the request url doesn't contain "wsapi", it doesn't get through) and I have fiddler running on the background at all times regardless of whether the API is used or not, and occasionally my system would slow down, so I would open task manager... and see fiddler hogging about 7 gigs of ram. Yes, seven gigs, almost half of my RAM, with the fiddler window being completely empty. Yes, empty. No records, none. Yet Fiddler is growing exponentially, should I forget it on for a few days without checking on its memory footprint.

It's something that has been there for ages, and not something I think about, as I normally just restart the program (or close and start it when I need it), but since I discovered it while I had some spare time, I thought I'd make a post about it, as the internet has been rather fruitless about it, although I can see a few posts which normally relate to garbage collection... but considering I have had the slowdown with 1,5 gigs of Fiddler memory with rest of the applications pushing it far over 16 gigs (swap file to the rescue), if it really is that, the garbage collector is doing an incredibly rotten job, as the resources are definitely needed by other applications.

I am very new to Fiddler and am needing some help monitoring some JSON messages. I normally use a test client from my pc to send json messages to a rest api endpoint on azure. There are various other applications sending messages to that endpoint too. How do i capture all the messages that reach the endpoint?

I want to autoinspect session if it allow by filter. If I try to put oSession.oFlags["X-Builder-Inspect"] = "1"; in a OnBeforeRequest() - autoinspect works, but it trying to inspect sessions that didn't allow by filter. So i tried to put oSession.oFlags["X-Builder-Inspect"] = "1"; in OnBeforeResponse() but then autoispect doesnt work. What's the reason? May be there is other ways to autoinspect allowed sessions?

I am trying to use 100% stack area chart and on this scenario it gives me overflow chart. Here for 2004 and 2011 all data are 0 (zero).
http://trykendoui.telerik.com/EjIw/2

 

In the company I work for, there is a .NET application developed using WCF. There are 2 parts - 1. Application  server and 2. A thick client - Both installed on the same machine. The application server is IIS.

I would like to capture all SOAP calls make by the client to the application server. I tried Fiddler, but it is not capturing traffic to localhost at the moment. Any way to capture the WCF calls made to the localhost by the windows thick client?

I tried to remove "loopback" from Tools - Fiddler Options - Connections : "ByPass Fiddler for URL's that with", but unable to do this. 

If fiddler doesn't do this any other software that does this? 

I've been using the hosts filter option extensively, to hide traffic from various sites (used for regular surfing).
It seems that the filter has a maximum length of 4096 characters - is that correct?

Shouldn't we be allowed to specify more than that?

I'm working with the owner of the firm where I work to track down the source of "DO_NOT_TRUST_FiddlerRoot" certificates that keep accumulating in his Personal cert store. We've also identified the "DO_NOT_TRUST_FiddlerRoot" dummy CA cert in his "Trusted Root Certification Authorities" store. We've been able to confirm that he does not have the Fiddler application installed on this computer. We've also been unable to find any of the FiddlerCore DLLs on his hard drives. Which leads me to believe that the FiddlerCore DLL has been merged into a stand-alone executable by using something like ILMerge.

We have a general idea of when the dummy CA cert was created, so we're starting to look at applications (particularly applications in the system's Startup folders) which were installed right about that time. But the question for the forum: is there any quick or easy way to identify which applications may have the FiddlerCore engine embedded in them?

Thanks in advance for any advice, suggestions!

Hello,

I want to use Fiddler to utilize HTTP/1.0 functionality which do not support "Host" header. Yet if I put http://10.10.10.10/ into Request Builder and choose "HTTP/1.0" from menu, it still puts "Host" header in. I want request coming out without that header at all. How do I do that?

Hi-

I was given a Fiddler trace (saz file) that illustrates a problem being experienced from a network in Eurorpe. This one user is reporting slow page loads.  Really really slow page loads.

The trace shows some requests returning a "result" of 0 rather than 200 response code, but most are returning 200.  This is the only known issue from over 40 other client work stations.  My immediate thought is to lay the blame on this single client instance.  But the trace (snippet below) is showing that the request was made and the server has received it.  Which makes the server look guilty here.  Except, I've not once been able to repro this issue from the US.  And 40+ other clients are not reporting the same issue.   I am trying to find out if, despite the server having received the request as shown, could this possibly be a client side issue? 

Request Count:   1
Bytes Sent:      1,807        (headers:1,025; body:782)
Bytes Received:  60        (headers:60; body:0)

ACTUAL PERFORMANCE
--------------

This traffic was captured on Thurs

ClientConnected:    23:30:52.348
ClientBeginRequest:    23:30:55.362
GotRequestHeaders:    23:30:55.362
ClientDoneRequest:    23:30:55.364
Determine Gateway:    0ms
DNS Lookup:         0ms
TCP/IP Connect:    0ms
HTTPS Handshake:    0ms
ServerConnected:    23:30:52.401
FiddlerBeginRequest:    23:30:55.364
ServerGotRequest:    23:30:55.364
ServerBeginResponse:    00:00:00.000
GotResponseHeaders:    00:00:00.000
ServerDoneResponse:    00:00:00.000
ClientBeginResponse:    00:00:00.000
ClientDoneResponse:    00:00:00.000


RESPONSE BYTES (by Content-Type)
--------------
~headers~: 60


Thanks in advance-

Help to change server request (RAW):

GET http://server.test.com/olea/? l=4530110&k=70d11cab74190ca973166e3aa9921ce1&n=4530110&e=eForwardActiveLite_v3.2&f=F0003&p=1,0.10000000,0.10000000,2681.08000000 HTTP/1.1
User-Agent: Microsoft Internet Explorer
Host: server.test.com
Pragma: no-cache

It is necessary to replace values 4530110 on 1234567