Tungstwenty edited this page Jul 18, 2012 · 2 revisions


Author(s): sven, credits to Tritonio_GR @xda-dev

Ranking: n/a

Speaking Name: deleted_wake_locks

Rationale: In the API available to android drivers it is advised to call wake_lock_destroy before freeing the memory of the wakelock struct that they created. This is done above all on shutdown, but also in a few situations where a driver is unloaded dynamically from the kernel. Whenever it happens, the destroyed wakelocks disappear from the list but their stats are added up to this pseudo-wakelock to the deleted_wake_locks. This allows knowing that a set of old wakelocks had a combined set of stats that this entry shows. The stats of this entry do not increase unless additional real wakelocks that have non-zero stats are destroyed.

Know actions: Since this is merely an entry that combines the activity of all the kernel wake locks that no longer exist, there's nothing that can be directly done to reduce this entry. The best course of action is to identify the wake locks that generate activity and that are later deleted, before that happens and they end up showing in a combined way on this entry.

Known conditions of occurence:
The Wifi driver is one known source for kernel wakelocks that are destroyed whenever the driver is unloaded (when Wifi is disabled manually or as part of the turn-off policy). Wakelocks such as wlan_rx_wake and wlan_wake, when the driver is unloaded, will no longer show up in the list and their stats be added to the deleted_wake_lock previous values.

Related wakelocks: