Probe overhead limit exceeded

[sanketplus]

While probing for a very simple flask app which appends a string into a global variable, I sometimes get following.

sanket@tfs:~/workspace/systemtap-python-tools$ sudo ./scripts/memtrace -x 4630 -t 60 -v
stap /home/sanket/workspace/systemtap-python-tools/scripts/memtrace.stp 60 -I /home/sanket/workspace/systemtap-python-tools/scripts/../tapset/python2 -x 4630 -d kernel -d /usr/lib/x86_64-linux-gnu/libssl.so.1.1 -d /lib/x86_64-linux-gnu/ld-2.27.so -d /lib/x86_64-linux-gnu/libdl-2.27.so -d /lib/x86_64-linux-gnu/libc-2.27.so -d /usr/lib/python2.7/lib-dynload/_json.x86_64-linux-gnu_d.so -d /usr/lib/python2.7/lib-dynload/_hashlib.x86_64-linux-gnu_d.so -d /usr/lib/python2.7/lib-dynload/_ssl.x86_64-linux-gnu_d.so -d /lib/x86_64-linux-gnu/libm-2.27.so -d /usr/lib/python2.7/lib-dynload/_ctypes.x86_64-linux-gnu_d.so -d /lib/x86_64-linux-gnu/libnss_files-2.27.so -d /usr/lib/x86_64-linux-gnu/libffi.so.6.0.4 -d /lib/x86_64-linux-gnu/libuuid.so.1.3.0 -d /lib/x86_64-linux-gnu/libz.so.1.2.11 -d /lib/x86_64-linux-gnu/libpthread-2.27.so -d /usr/lib/x86_64-linux-gnu/libcrypto.so.1.1 -d /usr/bin/python2.7-dbg -d /lib/x86_64-linux-gnu/libutil-2.27.so -D MAXSTRINGLEN=4096 -D MAXBACKTRACE=200 -D MAXMAPENTRIES=10240
WARNING: confusing usage, consider @entry($p) in .return probe: identifier '$p' at /home/sanket/workspace/systemtap-python-tools/scripts/memtrace.stp:10:21
 source:     delete alloc_bt[$p]
                             ^
ERROR: probe overhead exceeded threshold
WARNING: Number of errors: 1, skipped probes: 0
WARNING: /usr/bin/staprun exited with status: 1
Pass 5: run failed.  [man error::pass5]
Number of similar warning messages suppressed: 1.
Rerun with -v to see them.
Tip: /usr/share/doc/systemtap/README.Debian should help you get started.
Error running stap script (exit code 1). You may need to pass --py3.