Hello,
While working on Migration to last HC4.5 APIs and testing Client
Certificate (see another question on how to include tests for it), I
confirmed that the bug reported by Rainer was still here.
This bug has the following impact:
- Whenever you set "https.use.cached.ssl.context=false " which is
required for Client Certificate Testing, you end up :
- Replaying SSL Handshake on every sample while we shouldn't
- Losing KeepAlive
- Another thing he tackles is that fact that within Thread Group
iteration we reuse objects we shouldn't
IMO, we need to tackle it, looking at Rainer patch I agree with almost all
his proposals except for what I describe below.
Let's see use most common cases :
- 0/ We are testing HTTP, Rainer is correct saying that when we switch
to next iteration and are using KeepAlive we use the same connection while
we shouldn't , this would be PROBLEM A below
- 1/ We are testing HTTPS only without client certificate, then
https.use.cached.ssl.context=true is ok within 1 thread group iteration.
What would be unrealistic is the fact that SSL Handshake will not occur for
next iteration. Let's call this case PROBLEM A.
- 2/ We are testing HTTPS only WITH client certificate, then since
https.use.cached.ssl.context=false is needed we have a problem PROBLEM B.
*ASSUMPTION:*
First, I think that we should consider that Each Thread Group Iteration is
a new user, indeed, If one wants to make the same user loop, he can easily
add a Loop Controller as child of Thread Group and it's ok.
*So let's zoom to PROBLEM B first:*
- If we make the assumption above, part of the patch of Rainer can be
reused:
- Have a thread local hold the fact that reset occured, but Maybe
using JMeterVariables would be better particularly if one day we
decide to
switch to different model 1 VU == 1 Thread.
- What should be changed in Rainer patch is the SSL reset, indeed for
HC4.5 we need to close idle and expired connections to really reset SSL
State
- What I don't get about Rainer patch is wether we should do the
close on all HTTPCLIENT Instances of VUs or not. I think we should but It
would be great if another brain or more would confirm
*Let's zoom to PROBLEM A:*
In summary, whenever we make a new Thread Group iteration, we must start
with new connections and not reuse existing ones.
So Rainer patch looks ok to me.
But:
1/ I would personally set default to
-
reuse.http.connections=false
2/ I would not introduce reuse.http.client
3/ I would not as a consequence reset HttpClient as it is not needed
to reset state if I am not wrong and it would
introduce "initialization cost" in requests timing
What's your thoughts ?
--
Regards
Philippe M.
