On Mon, 1 Jun 2026 16:24:48 GMT, Ashay Rane <[email protected]> wrote:
>> Prior to this patch, every HTTP request created a new 16KB buffer for >> encoding the header, which is typically only a few hundred bytes long. >> This increased pressure on the garbage collector when the client created >> lots of requests. This patch instead makes the header encoder reuse the >> buffer that is created during the handling of the first request. >> >> The caveat, however, is that the downstream consumers of the header are >> asynchronous, so the encoder needs to take special care to ensure that >> it doesn't modify or invalidate the buffer after it hands the buffer >> over to the downstream asynchronous pipeline. To resolve this, this >> patch snapshots the buffer data into compact copies sized to the actual >> encoded length. Doing so makes the buffer immediately available for >> reuse via `clear()` and `limit()`. >> >> For typical requests, this reduces per-request allocation from 16KB to >> a few hundred bytes (i.e. the size of the compact copy of the encoded >> headers), with the 16KB encoding buffer allocated once per connection >> instead of once per request. >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > Ashay Rane has updated the pull request incrementally with one additional > commit since the last revision: > > Address PR comments > > 1. The number of HTTP headers impacts the frame count but not the size > of the cached header buffer. Updated the comment to reflect this and > simplified the test to send just two follow-on requests: one with 2 > headers and another with 300 headers (to ensure that the cached > header buffer stays the same even when multiple frames are required). > > 2. Removed Markdown formatting from comments. > > 3. Fixed year in copyright notices. @raneashay Your change (at version e5901bdc40d9ceebb7cd53d4dd9c5ddc43fd3ed4) is now ready to be sponsored by a Committer. ------------- PR Comment: https://git.openjdk.org/jdk/pull/30931#issuecomment-4633300562
