glib offers thread pools and it seems to support "exclusive" and "shared"
thread pools.
https://developer.gnome.org/glib/stable/glib-Thread-Pools.html#g-thread-pool-new
Currently we use "exlusive" thread pools but its performance seems to be
poor. I tried using "shared" thread pools and performance seems much
better. I posted performance results here.
https://www.redhat.com/archives/virtio-fs/2020-September/msg00080.html
So lets switch to shared thread pools. We can think of making it optional
once somebody can show in what cases exclusive thread pools offer better
results. For now, my simple performance tests across the board see
better results with shared thread pools.
Needs this as well:
--- qemu.orig/tools/virtiofsd/passthrough_seccomp.c 2020-09-16 20:21:13.168686176 +0200
+++ qemu/tools/virtiofsd/passthrough_seccomp.c 2020-09-22 14:01:38.499164501 +0200
@@ -94,6 +94,8 @@ static const int syscall_whitelist[] = {
SCMP_SYS(rt_sigaction),
SCMP_SYS(rt_sigprocmask),
SCMP_SYS(rt_sigreturn),
+ SCMP_SYS(sched_getattr),
+ SCMP_SYS(sched_setattr),
SCMP_SYS(sendmsg),
SCMP_SYS(setresgid),
SCMP_SYS(setresuid),