MIDAS workshop 22 Sep 2025, Konstantin Olchanski, TRIUMF

Wishlist and ongoing things in the MIDAS underbelly

1) big missing piece - "software QA infrastructure"

* nightly builds (kinda have them now, minus ROOT, python and javascript)
* nightly run memory sanitizer and thread sanitizer
* nightly static analyzer (have nightly doxygen for call graphs)
* nightly test coverage report (have "make coverage" from Ben)
* nightly copilot and chatgpt "AI code reviews" (yes)

other large projects have all this stuff. it's absense in MIDAS
is hard to hide. perl has "make test" since mid-1990-ies.

* why important:

a) stalled rework of db_delete(path,flag), to-be-removed "flag" argument
is used inconsistently, need a set of test cases to make sure
db_delete() does the right thing before rework and after rework.

b) stalled MIDAS-RPC layer rework, have standalone RPC test code,
needs to be added to "make test", but there is no "test framework".

c) recent change to odbxx (use of thread-local storage), I think
this changs breaks all multithreaded code, need a test case
to prove it either way.

2) ODB ongoing rework:

* main goal is to remove all recursive code, remove recursive locking,
 remove complex and brittle recursive locking code
 in db_lock_database() and db_unlock_database()
* eventually have separate read lock and write lock (per text book)
* eventually have efficient "write-protected odb" (have this now,
 but sometimes it is too slow)

3) history improvements:

* compressed history files
* faster read of history files (now: one read() per history record,
read a block of records or use mmap())
* reduce number of history files in the main subdirectory (move old files
to a different subdirectory, etc)

4) RPC improvements wishlist:

* rework mserver connection so it can be tunneled through ssh
* JSON-encoded RPC for C/C++-free MIDAS clients
* commit the RPC code rework that can transport std::string and std::vector

5) "other"

* rework and commit the cascade code from T2K/ND280
* implement memory limit for mhttpd, mlogger
* fix buglets in web pages (run start page, history editor page, etc)
* more std::string everywhere (needs std::string support in MIDAS RPC!)

K.O.