Re: [PATCH proxmox-backup 3/5] bin: proxy: periodically schedule fstrim on datastore's filesystems

["Fabian Grünbichler" <f.gruenbichler@proxmox.com>]

On March 19, 2026 4:02 pm, Christian Ebner wrote:
> On 3/19/26 3:36 PM, Christian Ebner wrote:
>> Run the fstrim command as scheduled job on datastores having a
>> schedule defined in the config.
>> 
>> This is done since by default the systemd service to execute fstrim
>> invokes the command with:
>> 
>> `/sbin/fstrim --listed-in /etc/fstab:/proc/self/mountinfo ...`
>> 
>> which however does not cover datastores created on top of a disk,
>> since these are mounted via systemd mount units. fstrim however only
>> evaluates the given list above up to the first non-empty file as
>> stated in the man page [0].
>> 
>> [0] https://www.man7.org/linux/man-pages/man8/fstrim.8.html
>> 
>> Fixes: https://forum.proxmox.com/threads/181764/
>> Signed-off-by: Christian Ebner <c.ebner@proxmox.com>
>> ---
>>   src/bin/proxmox-backup-proxy.rs | 59 +++++++++++++++++++++++++++++++++
>>   1 file changed, 59 insertions(+)
>> 
>> diff --git a/src/bin/proxmox-backup-proxy.rs b/src/bin/proxmox-backup-proxy.rs
>> index c1fe3ac15..1d375e69d 100644
>> --- a/src/bin/proxmox-backup-proxy.rs
>> +++ b/src/bin/proxmox-backup-proxy.rs
>> @@ -508,6 +508,7 @@ async fn schedule_tasks() -> Result<(), Error> {
>>       schedule_datastore_verify_jobs().await;
>>       schedule_tape_backup_jobs().await;
>>       schedule_task_log_rotate().await;
>> +    schedule_fstrim().await;
>>   
>>       Ok(())
>>   }
>> @@ -879,6 +880,64 @@ async fn schedule_task_log_rotate() {
>>       }
>>   }
>>   
>> +async fn schedule_fstrim() {
>> +    let config = match pbs_config::datastore::config() {
>> +        Err(err) => {
>> +            eprintln!("unable to read datastore config - {err}");
>> +            return;
>> +        }
>> +        Ok((config, _digest)) => config,
>> +    };
>> +
>> +    for (store, (_, store_config)) in config.sections {
>> +        let store_config: DataStoreConfig = match serde_json::from_value(store_config) {
>> +            Ok(c) => c,
>> +            Err(err) => {
>> +                eprintln!("datastore config from_value failed - {err}");
>> +                continue;
>> +            }
>> +        };
>> +
>> +        let event_schedule = match &store_config.fstrim_schedule {
>> +            Some(event_schedule) => event_schedule,
>> +            None => continue,
>> +        };
>> +
>> +        let worker_type = "fstrim";
>> +        if check_schedule(worker_type, event_schedule, &store) {
>> +            let mut job = match Job::new(worker_type, &store) {
>> +                Ok(job) => job,
>> +                Err(_) => continue, // could not get lock
>> +            };
>> +
>> +            if let Err(err) = WorkerTask::new_thread(
>> +                worker_type,
>> +                None,
>> +                Authid::root_auth_id().to_string(),
>> +                false,
>> +                move |worker| {
>> +                    job.start(&worker.upid().to_string())?;
>> +                    info!("executing fstrim on filesystem for {store}");
>> +
>> +                    let path = store_config.absolute_path();
>> +                    let result = proxmox_backup::tools::disks::fstrim(Path::new(&path))
>> +                        .map(|output| log::info!("{output}"));
> 
> Only realized now that this does not work since unprivileged, but this 
> needs to be run as root. So this needs additional rework...
> 
> Other open questions still remain though.

it would also need to do a lookup_datastore, since we want to register
fstrim as operation that blocks things like unmounting? which likely
means it should be implemented on top of Datastore, and not called
directly..

> 
>> +
>> +                    let status = worker.create_state(&result);
>> +
>> +                    if let Err(err) = job.finish(status) {
>> +                        eprintln!("could not finish job state for {worker_type}: {err}");
>> +                    }
>> +
>> +                    result
>> +                },
>> +            ) {
>> +                eprintln!("unable to start fstrim task: {err}");
>> +            }
>> +        }
>> +    }
>> +}
>> +
>>   async fn command_reopen_access_logfiles() -> Result<(), Error> {
>>       // only care about the most recent daemon instance for each, proxy & api, as other older ones
>>       // should not respond to new requests anyway, but only finish their current one and then exit.
> 
> 
> 
> 
> 
>