| author | Matti Laitinen <matti.t.laitinen@nokia.com> |
| Thu, 11 Feb 2010 15:32:31 +0200 | |
| changeset 2 | b9ab3b238396 |
| child 5 | 844b047e260d |
| permissions | -rw-r--r-- |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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<title>Server Threads Analysis</title> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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<link href="../../../book.css" rel="stylesheet" type="text/css"> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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</head> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<body> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<h3>Server Threads Analysis</h3> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<p> A typical Symbian application implementation pattern is based on a client-server model. The client requests a service, and the server does the actual work. As a result, the server parts of the application cause most of the CPU load.</p> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<p>The Symbian OS provides several system servers, such as file, font bitmap and database servers, which might be used by several applications concurrently. There might also be other application framework specific servers. In order to analyze the application characteristics properly, find out which servers the application uses. In addition, recognize how extensively the application under analysis really uses the servers, especially system ones.</p> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<p>If the thread overview shows that server threads cause high CPU load, the problem is not necessarily in the server implementation. If a more detailed analysis of the server implementation does not reveal any major improvement items, more focus has to be put on overall application characteristics. Things to consider include the following:</p> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<ul> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
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<li>Is client-server interaction rational? For example, frequently exchanged small messages cause overhead and decrease the application performance.</li> |
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Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<li>Are there nested client-server call chains? A long chain of servers utilizing services of other servers should be studied. For example, a top-level client makes a simple service request to a server that forwards the request to another server in multiple requests. As a result, a simple service request has been split up into several small requests resulting in a potential bottleneck in overall application performance.</li> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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</ul> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
changeset
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<p>In general, the goal should be to minimize unnecessary calls to servers. Multiple application requests should be grouped in a single server request whenever possible.<br> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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</p> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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<div id="footer">Copyright © 2009 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. <br>License: <a href="http://www.eclipse.org/legal/epl-v10.html">http://www.eclipse.org/legal/epl-v10.html</a></div> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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</body> |
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b9ab3b238396
Initial version of Performance Investigator under EPL
Matti Laitinen <matti.t.laitinen@nokia.com>
parents:
diff
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</html> |