PQ73005: PQ60569 CHANGED THE PLUGIN TO READ DATA IN CHUNKS OF 64K. IF THERESPONSE BODY IS LARGE (E.G 8MB), THIS CAN CAUSE PERFORMANCE HIT | |||||||||||||||||||||||||||||||||||||||||||
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![]() APAR status Closed as program error. Error description Prior to PQ60569 the plugin would allocate a buffer size of the content-length -- no matter how large -- and send the response body in one chunk. For customers who sent huge amounts of data this caused resource issues and performance issues if AFPA was enabled so a change went in to read the data in chunks of 64k instead of all at once. So in the testcase where the response body is 8 meg, this would add approximately 125 extra system calls to read the entire response body. As we cannot back out PQ60569 the solution is to add a configurable parameter which would allow the CU to specify the chunksize for reading the response body. The CU can tune this parameter to increase the performance realizing that larger chunk sizes may cause system resource issues.Local fix Problem summary **************************************************************** * USERS AFFECTED: All WebSphere Application Server users * **************************************************************** * PROBLEM DESCRIPTION: Reading the response body in 64k chunks * * causes performance issues for large * * response bodies. * **************************************************************** * RECOMMENDATION: * **************************************************************** The plugin would the read the response body in 64k chunks until all of the response data was read. This cause a performance problem for request whose response body contained large amounts of data. Customers need a way to specify the maximum chunk size to use when reading the response body.Problem conclusion The ResponseChunkSize attribute was added at the Config level in the plugin-cfg.xml so the customer can specify the maximum chunk size to use when reading the response body. Ex: <Config ResponseChunkSize="N"> where N equal the chunk size in kilobytes. If the content length of the response body is unknown a buffer size of Nk will be allocated and the body will be read in Nk size chunks until the entire body is read. If the content length is known then either then a buffer size of either content length or N (whichever is less) will be used to read the response body. A default of 64k will be used if the ResponseChunkSize is not set.Temporary fix Comments
APAR is sysrouted FROM one or more of the following: APAR is sysrouted TO one or more of the following: PQ73479 Modules/Macros
Publications Referenced
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Product categories: Software > Application Servers >
Distributed Application & Web Servers > WebSphere Application
Server > General
Operating system(s):
Software version: 00W
Software edition:
Reference #: PQ73005
IBM Group: Software Group
Modified date: Jul 12, 2003
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