Mailing-List: contact user-help@jmeter.apache.org; run by ezmlm
Precedence: bulk
Reply-To: "JMeter Users List" <user@jmeter.apache.org>
MIME-Version: 1.0
From: Malith Jayasinghe <malith.jayasinghe@gmail.com>
Date: Thu, 23 Nov 2017 09:34:02 +0530
Message-ID: <CALo8FP8eP0idpewxDGhyRQ6hh4Qx3azQPj16qxy1E2iAL1OBEA@mail.gmail.com>
Subject: Issues in JMETER Dashboard Latency Percentile Calculations
To: JMeter Users List <user@jmeter.apache.org>
Content-Type: multipart/alternative; boundary="94eb2c069734ce8109055e9e86b2"
archived-at: Thu, 23 Nov 2017 04:04:13 -0000

--94eb2c069734ce8109055e9e86b2
Content-Type: text/plain; charset="UTF-8"

Dear All,

We have been using JMETER extensively for performance testing.

All our performance reports are generated using the JMETER Dashboard.

Recently, we have found out that there is an issue in
the JMETER dashboard's *latency percentile calculation. *

There is a significant difference in the actual percentile values and the
values shown in the dashboard. We have verified this using "R" and in fact,
the values shown the JMETER aggregate report are correct. The values that
appear in the JMETER Dashboard are not.

We understand that JMETER Dashboard may be using a different algorithm
(approximation) for percentile calculation. However, the problem is that
that latency percentiles values calculated using this algorithm are not
accurate (at least for certain scenarios).

We have had a case where the Dashboard showing a 95% percentile value 1000
ms. However, the correct value was 321 ms.

The accuracy of percentile values are of utmost importance to us and we
would kindly ask you to look into this issue and release a patch if
possible.

If you can implement the same algorithm used in the aggregate report within
the dashboard that will resolve this issue.


Thanks

Malith Jayasinghe

--94eb2c069734ce8109055e9e86b2--