common/lru: fix race in lru #26164
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common/lru: fix race in lru #26164
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yperbasis
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Nov 14, 2022
[simplelru](https://github.com/hashicorp/golang-lru/tree/master/simplelru) is not thread safe. During the `Get` operation, the recentness of the accessed item is updated, so it is not a pure read-operation. Therefore, the mutex we need to protect the LRUs in txpool is a full mutex, not `RLock`. See erigontech/erigon#4679 (comment) and ethereum/go-ethereum#26164. Also, RWMutex has a performance overhead compared with the vanilla one (see, for example, golang/go#38813). Kudos to Martin Swende for pointing to the issue.
lochjin
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Nov 19, 2022
This fixes a problem in the SizeConstrainedLRU. The SCLRU uses an underlying simple lru which is not thread safe. During the Get operation, the recentness of the accessed item is updated, so it is not a pure read-operation. Therefore, the mutex we need is a full mutex, not RLock. This PR changes the mutex to be a regular Mutex, instead of RWMutex, so a reviewer can at a glance see that all affected locations are fixed. (cherry picked from commit 8334b5f)
dindinw
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Nov 19, 2022
common/lru: fix race in lru (ethereum#26164)
lochjin
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Nov 30, 2022
This fixes a problem in the SizeConstrainedLRU. The SCLRU uses an underlying simple lru which is not thread safe. During the Get operation, the recentness of the accessed item is updated, so it is not a pure read-operation. Therefore, the mutex we need is a full mutex, not RLock. This PR changes the mutex to be a regular Mutex, instead of RWMutex, so a reviewer can at a glance see that all affected locations are fixed. (cherry picked from commit 8334b5f)
shekhirin
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Jun 6, 2023
This fixes a problem in the SizeConstrainedLRU. The SCLRU uses an underlying simple lru which is not thread safe. During the Get operation, the recentness of the accessed item is updated, so it is not a pure read-operation. Therefore, the mutex we need is a full mutex, not RLock. This PR changes the mutex to be a regular Mutex, instead of RWMutex, so a reviewer can at a glance see that all affected locations are fixed.
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This fixes a problem in the
SizeConstrainedLRU. The SCLRU uses an underlying simple lru which is not thread safe.During the
Getoperation, the recentness of the accessed item is updated, so it is not a pure read-operation. Therefore, the mutex we need is a full mutex, not RLock.This PR changes the mutex to be a regular
Mutex, instead ofRWMutex, so a reviewer can at a glance see that all affected locations are fixed.Fixes: #26163