Bit-packing works on blocks larger than 128 longs #137811
Open
+301
−260
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Collaborator
|
Pinging @elastic/es-storage-engine (Team:StorageEngine) |
parkertimmins
approved these changes
Nov 10, 2025
Contributor
parkertimmins
left a comment
parkertimmins
left a comment
There was a problem hiding this comment.
Been looking at the numeric compression lately, so went ahead and gave this a review. 😃
Just a couple of nits, logic looks correct.
| private static final int BITS_IN_SIX_BYTES = 6 * Byte.SIZE; | ||
| private static final int BITS_IN_SEVEN_BYTES = 7 * Byte.SIZE; | ||
|
|
||
| private static final int BITBACK_BLOCK_SHIFT = 7; |
| assert numericBlockSize >= BITBACK_BLOCK_SIZE && (numericBlockSize & (BITBACK_BLOCK_SIZE - 1)) == 0 | ||
| : "expected to get a block size that a multiple of " + BITBACK_BLOCK_SIZE + ", got " + numericBlockSize; | ||
| this.blockSize = numericBlockSize; | ||
| this.encoded = new byte[numericBlockSize * Byte.SIZE]; |
Contributor
There was a problem hiding this comment.
nit: It be the same value, but would be clearer ifByte.SIZE were Long.BYTES`
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Existing bit-packing logic is customized to apply to blocks of 128 longs. For larger blocks that are multiple of 128, the bit-packing logic is extended to be applied to blocks of size 128 iteratively. This is expected to be a no-op, since the codec block size is 128, but unlocks experimenting with larger blocks.
Related to #136307