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Date: Tue, 22 Mar 2022 10:46:20 +0100 (CET)
From: Dietmar Maurer <dietmar@proxmox.com>
To: Proxmox Backup Server development discussion <pbs-devel@lists.proxmox.com>, 
 Wolfgang Bumiller <w.bumiller@proxmox.com>,
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Subject: Re: [pbs-devel] [RFC PATCH 0/5] fix #3935: refactor datastore
 locking to use tmpfs
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> - A "hashmap lock file": An in-memory file filled with robust-futex
>   where the group name simply gets hashed to get to a positioin in the
>   file. Hash clashes aren't an issue since all they'd do is cause
>   multiple groups to be guarded by the same lock, which wouldn't
>   technically be wrong.

Just want to note that above approach could lead to unexpected deadlocks with hash clashes, so I guess it is not that simple to get it right...