Crash in ntdll.dll

Yesterday I had a weird Cantabile crash - it said “crash in ntdll.dll”. I was just playing Keyscape - nothing weird or spectacular going on - and Cantabile had been running for several hours. Anyone who has had this? Ideas why? Would hate to see that happen in a live situation… First time ever I had a Cantabile crash (other than bugs in plugins I’ve developed myself :slight_smile: ).

Brad, you should have received the crash report!

Hi Tom,

Calls stack points to Topiary Beatz.


Given that this is a crash on a memory re-allocation my bet would be on a memory overrun by that plugin but you can’t rule out something else stomping over memory. (another plugin, Cantabile, system, etc…)

Doesn’t look like Cantabile was doing much in the prior 45 mins - just processing audio/midi/plugins.


Tx Brad, that’s good news - means it’s my fault (weird because the plugin had not been doing anything really) - it was loaded but I was just playing piano. Less good news is that such crashes are hard to find/debug :frowning:

I had another crash last nite - it didn’t even make a crash report as far I could see, but @brad if you did get one I’d be interested to know if it was the same issue. I’ll run the plugin idle for a couple of hours in debug mode in Cantabile and see if I can reproduce it that way.

From your other post, now I cannot help but wonder if it is Keyscape that is the real culprit eating up all the memory slots!


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Tonite I’ll try thinning the sampleset and see what happens…

This is probably linked to my other post about ridiculous number of file handles in Keyscape. Here’s the whole story so far:

  • I was puzzled about a memory related crash in Topiary Beatz - as a) I wrote the plugin myself and it doesn’t allocate memory dynamically and b) the plugin wasn’t even running when Cantabile crashed (from Cantabile pov it was running, but Beatz has a “run” mode which was off.
  • I’ve had 3 crashes, probably all related, and all happened in Cantabile sessions that had been running for several hours. I’ve run 100s of Cantabile sessions with this setlist and the only ones that have crashed were long ones.
  • I noticed (earlier) Keyscape takes long time ot load - even with my fast SSD. - and I have 10-ish instances in my preload setlist. I also saw, looking at memory use - weird stuff like 10G+ “reserved” memory, and 190000+ file handles used by Cantabile. Turns out those handles are used by Keyscape.
  • Talking to Keyscape support, I “thinned” the sample sets (advised for live use). That brings down my setlist load time to 25seconds instead of 5+ minutes. Memory use is WAY more reasonable now - but is still uses about 100000 file handles. I asked them to confirm whether this number of handles used is normal - waiting for a reaction on that one.
  • Ran the thinned setlist for over 24hrs now without crashes.

So… tentative conclusion: Keyscape - without thinning - is a memory monster which may or may cause problems. Will continue to monitor this!

(and live I’ll reboot after every break - just to be safe)


Whenever I see stuff like this it makes me wonder what they’re trying to achieve. I’m sure there’s some rationale for it but I don’t know what it is. I’ve also seen plugins that create thousands of threads - which seems even worse.

Anyway, thanks for the info. Good to know.

Same NTDLL crash for me using Keyscape

@AlanMHughes : do you use thinned sample sets? If not, try thinning them. I haven’t had this in over a week - since thinning …

I’ve had a few crashes over last few weeks but all of them happened when the laptop has not been rebooted for days, C3 has been running most of the time including sleep/wake modes, changing audio interfaces on the fly etc. Not sure if this is C3 fault, I think some plugin is more likely the culprit. Never had enough time to examine.

But I ALWAYS reboot before a live show and never got a crash during live gig this way.


The samples had been thinned for some time without any problems but at the time of the crash I had just reduced the number of voices. Maybe some memory handling issue.