map: fix TestMapBatch failing with ENOSPC for hash maps #1485
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The batch lookup API for hash maps returns ENOSPC when a bucket doesn't fit into the provided batch. This is unfortunate since user space has no way to figure out what the largest bucket size is. This makes the API very awkward to use. It also seems that hash tables don't deal well with sequential keys, hashing them into the same bucket with fairly high probability. Fix the flaky test by always making the batch size equal to the map size, which means we can never trigger ENOSPC. Also make the error message more descriptive. Fixes: cilium#1390 Signed-off-by: Lorenz Bauer <[email protected]>
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The batch lookup API for hash maps returns ENOSPC when a bucket doesn't fit into the provided batch. This is unfortunate since user space has no way to figure out what the largest bucket size is. This makes the API very awkward to use.
It also seems that hash tables don't deal well with sequential keys, hashing them into the same bucket with fairly high probability.
Fix the flaky test by always making the batch size equal to the map size, which means we can never trigger ENOSPC. Also make the error message more descriptive.
Fixes: #1390