Recalculate maxQueueSize based on shards count#578
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dkropachev wants to merge 1 commit intoscylladb:scylla-3.xfrom
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Recalculate maxQueueSize based on shards count#578dkropachev wants to merge 1 commit intoscylladb:scylla-3.xfrom
dkropachev wants to merge 1 commit intoscylladb:scylla-3.xfrom
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Currently maxQueueSize is 256 by default. Problem is that some hosts can have 1 shard, others can have 256 shards. While having cap of 256 pending requests for 1 shard host is ok. For host of 256 shards it is way to low. This commit scales maxQueueSize by number of shards, which allow default value works for hosts of any size.
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Hard objections:
setMaxQueueSize should also have the documentation updated.
Soft objections:
While the queue is global (per host I think), the description makes you think that the limits are per shard. This is not the case in the sense that one shard may use up the whole limit.
Regarding the name maybe maxQueueSizeFactor would be more descriptive now?
Different nodes will end up having different queue sizes if the number of shards is different.
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Currently
maxQueueSizeis256by default.Problem is that some hosts can have 1 shard, others can have
256shards.While having cap of
256pending requests for1shard host is ok, for bigger host of256shards it is way to low.This commit scales
maxQueueSizeby number of shards, which allow default value works for hosts of any size.Fix: #577