Runaway TIDS processes reported

A customer on Ubuntu 16 is using TIDS 1.5.2 (spun from the official source packages) and reports the following:

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We have a real problem with runaway tids processes. I enabled the provided systemd service, and it starts up OK, but then over time we accumulate tids processes, each of which is using as much CPU as it can (so the first uses 100% of one CPU, the second uses 100% of the second CPU, and then 100% of CPU is being spent on tids processes). restarting the tids service kills them all and then all is well again.

It's like tids is doing something bad after each transaction, and sitting in a tight loop rather than exiting?

example strace of one of these processes:

root@idp-01:~# strace -f -p 29901
strace: Process 29901 attached with 4 threads
strace: [ Process PID=29901 runs in x32 mode. ]
[pid 29904] futex(0x1fe354c, FUTEX_WAIT_PRIVATE, 1, NULL <unfinished ...>
[pid 29903] futex(0x1f2cb4c, FUTEX_WAIT_PRIVATE, 1, NULL <unfinished ...>
[pid 29902] futex(0x1e6afbc, FUTEX_WAIT_PRIVATE, 1, NULL^Cstrace:
Process 29901 detached
strace: Process 29902 detached
<detached ...>
strace: Process 29903 detached
strace: Process 29904 detached

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We've spun a build of the 2.1.1 package and have provided it to the customer for checking, but this should be documented for possible fixing.