When running HostBridge on the zIIP and executing an HB.js script that issues multiple hb.run() requests, unnecessary storage allocation occurs that can potentially cause an out-of-storage condition in the region HostBridge is running on (this is not a short-on-storage condition. The symptom will often be a 4xxx abend, i.e. 4093.
The memory is released when the script or service ends, so there is no ongoing memory leak. There is high memory usage for scripts that perform large numbers of hb.run() requests and only while those scripts run.
In order to correct this issue, you should replace modules HBR$DBAS, HBR$JSE, HBZJSEI, HBZJSER, and HBZJSET with the versions that can be found here: fetch.xmt