Right now, they seem to be deliverable on any thread, which can interrupt all sorts of things, sometimes with deleterious effect (cf, stlouis#922).
The most likely source of signals is probably when it spawns a (Unix) processes that then exits and a SIGCHLD is delivered to sled-agent, which sled-agent does with some non-trivial frequency. As a daemon, sled-agent could probably handle this better; perhaps disabling signals on all but one (dedicated) thread that blocks in sigwait or something similar.
Right now, they seem to be deliverable on any thread, which can interrupt all sorts of things, sometimes with deleterious effect (cf, stlouis#922).
The most likely source of signals is probably when it spawns a (Unix) processes that then exits and a
SIGCHLDis delivered tosled-agent, whichsled-agentdoes with some non-trivial frequency. As a daemon,sled-agentcould probably handle this better; perhaps disabling signals on all but one (dedicated) thread that blocks insigwaitor something similar.