A DESCRIPTION OF THE REQUEST :
There is a nice performance gain to be easily had, by controlling the GZIP compression level. However, GZIPOutputStream has no way to specify the compression level used by the underlying Deflater object.

JUSTIFICATION :
GZIPOutputStream is a widely used method of compression. I have found that compression level 3 offers substantial speed improvements over the default compression level. Speed gains of 50% seem to be easily achieved. For one data set tested, compression ran in less than half the time (2.2x faster), and the compression ratio was still excellent (4.6x compression vs 5.2x for default compression).

This small change will unlock a big performance win for many use cases.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
This request is simply asking for an additional constructor to be provided on java.util.zip.GZIPOutputStream class, which allows the compression level to be set by users. The current constructor has a hardcoded default level.

For example, the existing constructor “GZIPOutputStream(OutputStream out, int size, boolean syncFlush)” could be expanded as “GZIPOutputStream(OutputStream out, int size, boolean syncFlush, int compressionLevel)”.

CUSTOMER SUBMITTED WORKAROUND :
There is a similar bug which neglects to indicate the importance of the performance issue at hand. It suggests a suboptimal, license-restricted workaround. Please see: https://bugs.openjdk.java.net/browse/JDK-4452735

This is a great time to add the proper fix into the JDK.