address bad usage of TST #4048
address bad usage of TST #4048
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lib/core/tree.js
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| 94, 86, 15, 9, 56, 25, 38, 49, 12, 73, 24, 60, | ||
| 46, 11, 14, 83, 40, 52, 13, 21, 48, 30, 45, 10, | ||
| 53, 5, 59, 44, 35, 16, 36, 32, 0, 51, 82 | ||
| ] |
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Can you move it to a separate file, or can it be easily generated by a script?
lib/core/tree.js
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| // wellknownHeaderNames.forEach((key, idx) => { | ||
| // indexes.push(idx) | ||
| // }) | ||
| // randomIndexOfWellknownHeaderNames = shuffleArray(indexes) |
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why is this commented out? Can you nmove this to a script or another js file instead?
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I think we do not want any potential instable performance, right? (even the chance is low :) ) so I take a snapshot of one randomized insertion order that works well
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Maybe I just remove them from codebase outright and put it the PR
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@metcoder95 could you help move this forward |
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If not properly shuffled to balance the left and right sides, it will cause a bad case and further degrade performance. This is similar to the problem with binary trees. |
Given the array is sorted, randomly retrieving item from it and inserting to a TST/Binary search tree should yield a balanced tree. And the bottom line is that we definitely don't want to insert items to a TST in order because this is the worst case of this data structure. Maybe I can print out the TST and do a comparison? I did a non formal one before and it turned out that when searching for |
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Seems CI is not happy, can you try to rebase with |
This relates to performance of parseHeaders
Rationale
Inserting keys to TST in order yields the worst performance of this data structure. It is similar to inserting keys to a binary search tree in order makes it degenerate to a link list.
Randomize the insertion order simply works, but we do not want any potential instable performance, so I take a snapshot of one randomized insertion order that works well
Changes
Randomize the insertion order of the well known header keys
Features
N/A
Bug Fixes
N/A
Breaking Changes and Deprecations
N/A
Status