backup mail report says INTERRUPTED but it's not ?
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@Bastien-Nollet new day without false INTERRUPTED

the scrutiny of backup email reports made me find a new bug in backups (not reports this time)
i'll create a new topic about the dreaded BACKUP FELL BACK TO A FULL --> can provoke it on purpose ! -
Thanks @Pilow for the tests.
We'll have to investigate this to fix it more properly than adding a ugly delay.
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@Bastien-Nollet another good day
I think i'll swap to feedback if problem is back than problem is not here anymore


on your side to find something sexier than delay ^^' but it seems to be a race condition
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Hi @Pilow,
Thanks again for the feedback, I think now we have enough data to be sure it's indeed a race condition.
We noticed that the log you sent earlier in this topic is a backup job using a proxy. Could you tell if the backup jobs that ended up with a wrong status in the report were all using a proxy, or not all of them?
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@Bastien-Nollet 100% of our backup jobs are done by proxy
we offload that of main XOA that is purely for administration/management -
Hi @Pilow,
I've done some more testing and looked at the code, and I wasn't able to reproduce this behaviour once. It's also unclear to me why it can happen.
We may just add the delay as you did, but 10s is probably too long. Could you try to replace it by a 1s delay instead, and tell us if it's enough?
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@Bastien-Nollet okay i'll do that tonight and will report back
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26 backups in a row without interruption, spanning 2 days
And i'm on the 1 second fixguess it is enough...
@Bastien-Nollet said in backup mail report says INTERRUPTED but it's not ?:
I've done some more testing and looked at the code, and I wasn't able to reproduce this behaviour once. It's also unclear to me why it can happen.
I didn't tell but my Remotes are S3 Remotes... could it be because of that ?
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Thanks again @Pilow
I don't think the remotes being S3 changes something here.
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@Bastien-Nollet oopsy.
sadly, INTERRUPTED is back....
this is what I see in the backup report (a backup job of 12VMs to same S3 remote, only 1 interrupted...)


backup JOB in XOA is all green :


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Ok so 1s is slightly not enough, thanks for the update.
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@Bastien-Nollet another interrupted today.
I'll add one second by one second till I see it disappear.just modified to 2s delay.
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@Bastien-Nollet said in backup mail report says INTERRUPTED but it's not ?:
Ok so 1s is slightly not enough, thanks for the update.
Reply
still had issues with 2 sec delay.
it has now been 2 days with 3 sec delay, and no more. could be the sweet spot
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We're still carrying a bit of investigations to see if we can find the cause of the problem, but if we don't find it we'll add this delay.
Thanks @Pilow for the tests once again

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We just merged the delay: https://github.com/vatesfr/xen-orchestra/pull/9400
We increased it to 5s to have a security margin, as the optimal delay may not be the same on different configurations.
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@Bastien-Nollet many thanks
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Hey,
sadly issue seems to still exist...


I had 3 backup jobs running at the same time, all of them went into status "interrupted" at the exact same timestamp without me doing anything.
Xen Orchestra did not crash, XO VM has enough RAM, no OOM errors in log or similar.Interestingly the XO VM seems to still send data to the backup remotes even though the jobs show status interrupted.
This exact same issue happened 1 more time in the past but I thought maybe it is only a one-time-hiccup which is why I did not report it here at that point.
Issue first occurred somewhere around the release of XO6, before the XO6 I never had this kind of issue.
Best regards
//EDIT:
maybe to add some relevant info here. I am using XO from sources on Debian 13, NodeJS 24,
Commit fa110ed9c92acf03447f5ee3f309ef6861a4a0d4 ("feat: release 6.1.0").//EDIT2: Oh I just read in the initial post of this thread that on Pilow's end XO GUI reported success for the backup tasks but the emails indicated otherwise.
In my case the tasks also have status "interrupted" in XO GUI (and in the emails aswell as shown via screenshots).//EDIT3: I checked Xen Orchestra logs at the timestamp the backup jobs went into "interrupted" status, please find the log file attached below.
xo-log.txt
Based on the log file it looks like the Node JS process went OOM?
This is really strange as my XO VM has quite a lot of resources (8 vCPU, 10GB RAM). I checked in htop on the XO VM and it never went above 5GB during backups...//EDIT4: I did some research and found that some people had success with limiting their Node JS heap via environment variable.
I setexport NODE_OPTIONS="--max-old-space-size=6144"and will check if that fixes the issue for me.
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@MajorP93 said in backup mail report says INTERRUPTED but it's not ?:
Hey,
sadly issue seems to still exist...


I had 3 backup jobs running at the same time, all of them went into status "interrupted" at the exact same timestamp without me doing anything.
Xen Orchestra did not crash, XO VM has enough RAM, no OOM errors in log or similar.Interestingly the XO VM seems to still send data to the backup remotes even though the jobs show status interrupted.
This exact same issue happened 1 more time in the past but I thought maybe it is only a one-time-hiccup which is why I did not report it here at that point.
Issue first occurred somewhere around the release of XO6, before the XO6 I never had this kind of issue.
Best regards
//EDIT:
maybe to add some relevant info here. I am using XO from sources on Debian 13, NodeJS 24,
Commit fa110ed9c92acf03447f5ee3f309ef6861a4a0d4 ("feat: release 6.1.0").//EDIT2: Oh I just read in the initial post of this thread that on Pilow's end XO GUI reported success for the backup tasks but the emails indicated otherwise.
In my case the tasks also have status "interrupted" in XO GUI (and in the emails aswell as shown via screenshots).//EDIT3: I checked Xen Orchestra logs at the timestamp the backup jobs went into "interrupted" status, please find the log file attached below.
xo-log.txt
Based on the log file it looks like the Node JS process went OOM?
This is really strange as my XO VM has quite a lot of resources (8 vCPU, 10GB RAM). I checked in htop on the XO VM and it never went above 5GB during backups...It may be due to RSS memory requirements suddenly spiking, for NodeJS when it goes under load, running Xen Orchestra and backup operations (depending on where used can be particularly heavy).
@bastien-nollet @florent @olivierlambert Maybe worth looking into memory loads, for the NodeJS process when running heavy operations, for Xen Orchestra. Maybe necessary to contribute fixes, optimisations and/or medium to long term switch from NodeJS to something else.
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@majorp93 Hereâs a polished, forumâready version you can paste directly into your thread. Itâs written to be clear, technical, and helpful without sounding accusatory or speculative.
Proposed FollowâUp Post
After digging deeper into the behavior, Iâm increasingly convinced this isnât an XO bug but a Node.js 24 memory issue. The pattern matches a known problem with newer V8 versions used in Node 22+ and especially Node 24.
A few points that line up:- All backup jobs fail at the exact same timestamp
That usually means the worker process handling the backup pipeline disappeared abruptly. XO marks the job as âinterruptedâ when the process vanishes without a clean shutdown. - No crash logs appear
If the kernel OOMâkills the Node worker, it dies instantly and doesnât get a chance to write any logs. This is normal for OOM kills. - Nodeâs memory usage looks normal, but thatâs misleading
Tools like htop only show the JavaScript heap. V8 allocates a lot of memory outside the heap (JIT pages, array buffers, code space, etc.), and these donât show up in the usual metrics. With Node 24, these âhiddenâ allocations can spike high enough to trigger an OOM kill even when the heap looks modest. - The issue only started after upgrading to Node 24
Same VM, same RAM, same XO commit, same backup jobs. The only change was the Node version. Node 24 uses a newer V8 engine that is known to have higher RSS usage and more aggressive memory behavior under heavy async workloads like backups. - XOâs backup pipeline is exactly the kind of workload that triggers this
Large streams, compression, encryption, S3 multipart uploads, and lots of concurrent async operations all stress V8âs memory allocator. This makes RSS spikes much more likely.
Conclusion
Everything points to Node.js 24 being the root cause. The worker is likely being OOMâkilled by the kernel due to RSS spikes outside the JS heap, and XO reports the resulting incomplete job as âinterrupted.â
Suggested next steps
Try downgrading to Node 20 LTS, which is what XO from sources has historically been tested against.
Alternatively, run Node with a capped heap, for example:
Code
--max-old-space-size=4096
This forces earlier garbage collection and can reduce RSS spikes.
Or increase the VMâs RAM if downgrading isnât an option.
This should help confirm whether the issue is tied to the Node version.
- All backup jobs fail at the exact same timestamp
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@john.c said in backup mail report says INTERRUPTED but it's not ?:
--max-old-space-size=4096
Yeah I already set "--max-old-space-size" as mentioned in my post. I set it to 6GB. I will re-test and post findings to this thread.
I already checked "dmesg" and "journalctl -k | cat". There was no OOM entry. So the kernel OOM killer is not involved in this.
Only the Node JS / Xen Orchestra log indicated the memory heap / OOM issue.