Hi,
java.util.zip.Adler32/CRC32 do not have update method that accepts
ByteBuffer.
As of JDK7, you have to copy the content of the ByteBuffer into a
byte[], then
invoke Adler32/CRC32.update() method, which might have significant
performance
impact for some applications. Here I'm proposing to add two update
methods in
j.u.z.Adler32 and CRC32 classes respectively to address this issue.
Here is the webrev
http://cr.openjdk.java.net/~sherman/7109837/webrev
Attached is the result of TimeChecksum.java, which also serves as a
simple Benchmark.
Thanks!
Sherman
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sherman@sherman-linux:~/Workspace/jdk8_bugfix/test/java/util/zip$ java
TimeChecksum
---------- Adler32 ----------
Warmup... 59,535 59,495 59,948
Length byte[](ns/len) ByteBuffer(direct) ByteBuffer
1 13,409,610 2,990,525 ( 77%) 13,196,357 ( 1%)
checksum=bd00bd
2 5,808,804 1,664,460 ( 71%) 7,069,931 ( -21%)
checksum=19000d3
4 3,009,793 858,267 ( 71%) 3,516,799 ( -16%)
checksum=55f01fe
8 1,560,870 508,546 ( 67%) 1,754,650 ( -12%)
checksum=11cc03d4
16 792,323 298,697 ( 62%) 931,902 ( -17%)
checksum=40fb071b
32 430,367 185,262 ( 56%) 487,747 ( -13%)
checksum=ed2b0e1d
64 242,277 123,685 ( 48%) 277,898 ( -14%)
checksum=d0601df1
128 147,870 96,570 ( 34%) 164,493 ( -11%)
checksum=29d13ac0
256 107,230 80,315 ( 25%) 114,297 ( -6%)
checksum=20807ab7
512 85,729 73,765 ( 13%) 90,236 ( -5%)
checksum=feb1face
1024 74,593 67,872 ( 9%) 77,241 ( -3%)
checksum=7721ffb7
2048 71,558 68,599 ( 4%) 72,673 ( -1%)
checksum=717c0800
4096 70,053 64,908 ( 7%) 67,246 ( 4%)
checksum=53b5fbe1
8192 62,689 60,908 ( 2%) 62,205 ( 0%)
checksum=7ae5e6b3
16384 60,721 59,802 ( 1%) 60,920 ( 0%)
checksum=89e1b861
---------- CRC32 ----------
Warmup... 100,600 101,373 100,795
Length byte[](ns/len) ByteBuffer(direct) ByteBuffer
1 10,929,099 3,562,762 ( 67%) 13,328,815 ( -21%)
checksum=10d5102a
2 5,811,664 1,846,604 ( 68%) 6,924,621 ( -19%)
checksum=fd7d461a
4 3,048,740 968,395 ( 68%) 3,522,863 ( -15%)
checksum=a1ab61ba
8 1,605,356 539,462 ( 66%) 1,778,894 ( -10%)
checksum=cdc2506e
16 859,704 318,999 ( 62%) 926,758 ( -7%)
checksum=1c3db3a3
32 474,646 216,487 ( 54%) 489,307 ( -3%)
checksum=19bbc99e
64 282,917 157,252 ( 44%) 280,958 ( 0%)
checksum=df43e0e0
128 195,853 127,730 ( 34%) 164,068 ( 16%)
checksum=5fa8c160
256 147,025 116,742 ( 20%) 113,715 ( 22%)
checksum=854200ac
512 121,620 108,233 ( 11%) 90,232 ( 25%)
checksum=1b6cc88e
1024 110,529 106,890 ( 3%) 77,241 ( 30%)
checksum=1456003f
2048 105,115 103,971 ( 1%) 72,716 ( 30%)
checksum=187766b0
4096 102,661 103,858 ( -1%) 67,646 ( 34%)
checksum=91c34ea3
8192 101,280 103,494 ( -2%) 62,359 ( 38%)
checksum=2b8921aa
16384 104,444 105,407 ( 0%) 61,126 ( 41%)
checksum=6f921ec0
