On 10/07/2018 22:02, Brent Christian wrote:
Hi,
Please review this change to disable the file canonicalization cache
by default.
Bug:
https://bugs.openjdk.java.net/browse/JDK-8207005
From the bug report:
"The file canonicalization cache was added back in JDK 1.4.2 in order
to improve startup time.
The cache has long-standing correctness issues (JDK-7066948, for
example). For this reason, it has been desired to disable the cache by
default, but the increase to startup time was undesirable.
Recent JDK releases have removed usages of the cache, in particular
from FilePermission (JDK-8164705 in JDK 9). This reduced usage of the
canonicalization cache should also reduce the startup effect of
disabling the cache by default. Measurements support this. Previous
measurements showed the startup effect of disabling the cache on Linux
to be 3-6%, depending on the specific benchmark. The same comparison
performed last month now shows no startup change on Linux.
The file canonicalization cache can still be enabled by setting the
"sun.io.useCanonCaches" system property. This is merely a change to
the default value."
Happy to see this disabled as it has always been problematic. The patch
looks okay although you don't of couse need to set the initial values to
false.
-Alan
