influxdb 1.7.6 consumes much more memory then 1.7.4

Hello,

some days ago I upgraded to influxdb 1.7.6 on Ubuntu Bionic amd64 platform (KVM VM on Intel Nuc) and I noticed that the memory usage increased after some time. My notmal installation uses 17GB virtual memory but only 750-800MB RES mem. In 1.7.6 at some certain point in time (roughly the same on both days I noticed it) the RES mem starts to grow and ended up on 2,7GB. Also VIRT growed up to 20GB. After restart it restored to the 750-800MB for some time before it increases again. This happened multiple times
See graph here:


Then yesterday I reinstalled 1.7.4 on that machine and as you can see there is no such effect anymore. So something is strange here ...
You can also see that VIRT mem stays at 17GB.

I was not able to see anything special in the logs, just "normal stuff". I noticed some other issues here from the last time telling about memory issues, but I can not tell which of them may be connected.

If I can collect more details please tell me how and I will be happy to support.

No source file, test, or entry point is named. Begin by reproducing the reported memory growth while comparing InfluxDB 1.7.6 with 1.7.4 on Ubuntu Bionic amd64; done means identifying a reproducible cause or narrowing the missing diagnostic data.

Written by the indexing model from the issue text.