On 23/07/2020 18:18, Volker Simonis wrote:
Hi,
can I please get some reviews for the following small enhancement
which will allow you to configure different zlib implementations at VM
start-up and get up to 100% better throughput for compression and
about 50% better throughput for decompression (depending on the
selected zlib implementation). We're using a similar change
productively in Amazon since quite a while with good results on
compression/decompression heavy workloads.
As usual, my write-up is moch longer and much more complex than the
change itself :)
Yes, this needs discussion and agreement before starting an RFR. As
you've summarized in the JIRA issue, we have configure
--with-zlib=system and --with-zlib=bundled today. The former is the way
to build when what to make it possible to use an alternative zlib. The
new requirement that I think you are brining up is the case where
someone wants to use several zlib libraries at the same time, because
they somehow know that one version has superior performance than the
other on some functions. I think it's reasonable to ask if the JDK
really needs to support this complexity. I could imagine testing or
support folks in tears when they see the implications of this. Have you
looked at alternatives that would benefit other users of zlib, e.g. an
interposer that dispatches to the appropriate zlib based on configuration?
-Alan
