Hi Claes,
Your proposed changes to ParseUtil look reasonable
to me, though I had to carefully compare the characters
in the range (c >= '&' && c <= ':') with the
L_ENCODED / H_ENCODED masks to convince myself
that there was no behavior change to
ParseUtil::firstEncodeIndex.
I wonder whether this would deserve some additional
comment - though I'm not sure how it could be formulated.
Given the sensitivity of the impacted code maybe it would
be prudent to wait for a second review before pushing.
best regards,
-- daniel
On 14/02/2018 15:30, Claes Redestad wrote:
Hi,
as a means to improve startup in some applications, please review this
set of small improvements to improve both interpreted and compiled
performance of creating and handling certain jar URLs. Some of the
changes in sun.net.www.ParseUtil::encodePath have a small, positive
effect when dealing with other types of path resources.
Bug: https://bugs.openjdk.java.net/browse/JDK-8197849
Webrev: http://cr.openjdk.java.net/~redestad/8197849/jdk.00/
This shaves off a percent or so of the total bytecode execution in a few
of our startup tests:
- ParseUtil::encodePath cost is reduced ~20% during startup, averaging
~10-15% faster for typical inputs after JIT. Weird examples like paths
only consisting of slashes and dots can be seen to take a small hit due
to not getting special treatment.
- ParseUtil::canonizeString cost on startup reduced by 50% (~15%
improvement after JIT) for typical inputs by adding a test to return
directly if there's no need to "canonize" the string (which is typically
always the case for well-formed jar files). I added a sanity test to
ensure I didn't accidentally change semantics of cases that would lead
to canonicalization.
- Removed a couple of unnecessary allocation in
sun.net.www.protocol.jar.Handler. Maybe there are some good reasons not
to make ParseUtil a final utility class with only static methods and a
private constructor, though...
Thanks!
/Claes
