I use Mailspring for six email accounts, and have noticed that
mailsync.exe creates a lot of handles (the handle counter I have enabled in Process Hacker keeps going up; sometimes I reckon about 100k handles for all the mailsync processes in total). These handles will go away on restarting MailSpring (which, in turn, restarts all the
I have attached to a couple of processes via windbg and found that they use 15k and 25k event handles, respectively. Not sure if this is during normal operation or not, but I believe that the event handles are leaking.
Steps to reproduce the behavior:
mailsync.exerunning for several days
- Attach to a
mailsync.exeinstance via windbg
- Enter a command
- Note the event handle count
In one case, I had the following metrics:
Type Count None 10 Event 26910 Section 1 File 28 Directory 4 Mutant 3 WindowStation 2 Semaphore 31 Key 17 Thread 18 Desktop 1 IoCompletion 7 TpWorkerFactory 5 ALPC Port 4 WaitCompletionPacket 14
mainsync.exe shouldn’t leak resources even if running for several days.
- OS and Version: Windows 10 2004
- Installation Method: via Windows installer
- Mailspring Version: 1.8.0-8983dca2
I’ve found a GitHub issue mentioning a similar leak, marked as fixed in 2017: Mailsync leaks handles · Issue #388 · Foundry376/Mailspring · GitHub
Though I still observe the leaks (have to restart Mailspring every several days to reset the handle counter).