Hi Jaikiran
On Jun 30, 2021, at 12:15 PM, Jaikiran Pai
<[email protected]<mailto:[email protected]>> wrote:
Hello Lance,
On 29/06/21 11:31 pm, Lance Andersen wrote:
I ran your current test 150 times and the max runtime was 25 seconds, most
cases were in the 18-20 second range on our slower test boxes.
Thank you for running those tests. Do you think those timings are good enough
to let that test stay as a regular automated jtreg test, in tier1? I'm guessing
this falls in tier1? I haven't yet looked in detail the tier definitions of the
build.
These tests run as part of tier2.
The time for the test run is reasonable .
As part of looking at what happens with a file whose deflated size is > 2gb, I
would add a specific test which is a manual test to validate that there is no
issue when we cross the 2gb threshold.
I added a (manual) test to see what happens in this case. I have committed the
test as part of this PR just for the sake of reference. The test is named
LargeCompressedEntrySizeTest. The test uses ZipFS to create a (new) zip file
and attempts to write out a zip entry whose deflated/compressed size is
potentially greater than 2gb. When I run this test case, I consistenly run into
the following exception:
test LargeCompressedEntrySizeTest.testLargeCompressedSizeWithZipFS(): failure
java.lang.OutOfMemoryError: Required array length 2147483639 + 419 is too large
at
java.base/jdk.internal.util.ArraysSupport.hugeLength(ArraysSupport.java:649)
at
java.base/jdk.internal.util.ArraysSupport.newLength(ArraysSupport.java:642)
at
java.base/java.io.ByteArrayOutputStream.ensureCapacity(ByteArrayOutputStream.java:100)
at
java.base/java.io.ByteArrayOutputStream.write(ByteArrayOutputStream.java:130)
at
java.base/java.util.zip.DeflaterOutputStream.deflate(DeflaterOutputStream.java:252)
at
java.base/java.util.zip.DeflaterOutputStream.write(DeflaterOutputStream.java:210)
at
jdk.zipfs/jdk.nio.zipfs.ZipFileSystem$DeflatingEntryOutputStream.write(ZipFileSystem.java:2016)
at java.base/java.io.FilterOutputStream.write(FilterOutputStream.java:108)
at
LargeCompressedEntrySizeTest.testLargeCompressedSizeWithZipFS(LargeCompressedEntrySizeTest.java:104)
which to me is understandable. Is this what you and Alan wanted tested/checked?
In its current form I don't see a way to write out a entry whose deflated size
exceeds 2gb, unless the user/caller use the "useTempFile=true" option while
creating the zip filesystem. FWIW - if I do set this "useTempFile=true" while
creating that zip filesystem, in the LargeCompressedEntrySizeTest, that test
passes fine and the underlying zip that is created shows a compressed/deflated
size as follows:
unzip -lv JTwork/scratch/8190753-test-compressed-size.zip
Archive: JTwork/scratch/8190753-test-compressed-size.zip
Length Method Size Cmpr Date Time CRC-32 Name
-------- ------ ------- ---- ---------- ----- -------- ----
2147483649 Defl:N 2148138719 0% 06-30-2021 21:39 52cab9f8 LargeZipEntry.txt
-------- ------- --- -------
2147483649 2148138719 0% 1 file
I understand that Alan's suggestion holds good and we should have some logic in
place which switches to using a temp file once we notice that the sizes we are
dealing with can exceed some threshold, but I guess that is something we need
to do separately outside of this PR?
Yes the intent would be to add some logic, which might need to be under a
property (for now) to specify the size for when to use a temp file vs BAOS.
Having the value configurable via a property might give us some flexibility for
experimentation.
I don’t see why this PR could not be used for this (as it would provide a more
complete solution)
Best
Lance
-Jaikiran
[cid:E1C4E2F0-ECD0-4C9D-ADB4-B16CA7BCB7FC@home]
Lance Andersen| Principal Member of Technical Staff | +1.781.442.2037
Oracle Java Engineering
1 Network Drive
Burlington, MA 01803
[email protected]<mailto:[email protected]>
