> I would like a review of an update to the GCM code. A recent report showed > that GCM memory usage for TLS was very large. This was a result of in-place > buffers, which TLS uses, and how the code handled the combined intrinsic > method during decryption. A temporary buffer was used because the combined > intrinsic does gctr before ghash which results in a bad tag. The fix is to > not use the combined intrinsic during in-place decryption and depend on the > individual GHASH and CounterMode intrinsics. Direct ByteBuffers are not > affected as they are not used by the intrinsics directly. > > The reduction in the memory usage boosted performance back to where it was > before despite using slower intrinsics (gctr & ghash individually). The > extra memory allocation for the temporary buffer out-weighted the faster > intrinsic. > > > JDK 17: 122913.554 ops/sec > JDK 19: 94885.008 ops/sec > Post fix: 122735.804 ops/sec > > There is no regression test because this is a memory change and test coverage > already existing.
Anthony Scarpino has updated the pull request incrementally with one additional commit since the last revision: another comment update ------------- Changes: - all: https://git.openjdk.org/jdk/pull/11121/files - new: https://git.openjdk.org/jdk/pull/11121/files/340ab22f..99e350b2 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=11121&range=03 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11121&range=02-03 Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/11121.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11121/head:pull/11121 PR: https://git.openjdk.org/jdk/pull/11121
