During the build meson attempts to distribute the workload of multiple
sub-projects across all available CPUs and parallelize each build within
those projects, resulting in an NxN task generation.
This process could potentially overload the CI systems, leading to
potential failures (see for example issue #202).
To mitigate this, always use --jobs=1 during the CI run, which
serializes the build of sub-projects and restricts the level of
parallelization to N.
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
If we try to cross-build scx on builders with older versions of system's
linux headers (such as those provided by linux-libc-headers in older
releases of Ubuntu), we may hit build failures, due to the different
kernel ABI, such as:
error: invalid use of undefined type ‘struct btf_enum64’
To address this, introduce a new build option called "kernel_headers"
that allows to specify a custom path for the kernel headers required
during the build process.
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Build fails with sccache.
- Update meson-scripts/build_bpftool to support sccache. Unfortunately, this
isn't enough.
- Update README to warn about sccache and add the instruction to disable it
for buliding scx.
- Also add ⚠️ to make boot loader update step more prominent in arch
installation instruction.
Synchronize stragglers.
- Bug fix in __COMPAT_read_enum().
- A cosmetic difference in scx_qmap.bpf.c.
- Stray 'p' when calling getopt() in scx_simple.c.
After this the kernel tree and scx repo are in sync.
In rusty_select_cpu(), if a task is WAKE_SYNC, we'll currently migrate
the task to that CPU if there are any idle cores on the system. As in
[0], this condition is insufficient, as there could be idle cores
elsewhere on the system, but still tasks piled up on a single local DSQ.
Let's add a condition that the local DSQ has to be empty in order to
apply the WAKE_SYNC migration.
Before patch:
[void@maniforge src]$ hackbench
Running in process mode with 10 groups using 40 file descriptors each (== 400 tasks)
Each sender will pass 100 messages of 100 bytes
Time: 0.433
With patch:
[void@maniforge src]$ hackbench
Running in process mode with 10 groups using 40 file descriptors each (== 400 tasks)
Each sender will pass 100 messages of 100 bytes
Time: 0.035
Signed-off-by: David Vernet <void@manifault.com>
Change the upper bound of ineligible duration (LAVD_ELIGIBLE_TIME_MAX).
The updated (2x increased) upper bound reflects the distribution of
tasks' eligible_delta_ns better.
Signed-off-by: Changwoo Min <changwoo@igalia.com>
Change the calculation of the run_frequence using the wait_period from
the last time the task yielded CPU to this time when the task is
running. The old implementation measures the time interval between the
last stopping and the current running and increases run_freq without
reason.
Signed-off-by: Changwoo Min <changwoo@igalia.com>
Change the last_{start/stop/wait/wake}_clk in task_ctx to
last_{running/stopping/quiescent/runnable}_clk, matching with state
transition names. In addition, add comments and reorder fields in
task_ctx for readability.
Signed-off-by: Changwoo Min <changwoo@igalia.com>
Sync from kernel to receive new vmlinux.h and the updates to common headers.
This includes the following updates:
- scx_bpf_switch_all() is replaced by SCX_OPS_SWITCH_PARTIAL flag.
- sched_ext_ops.exit_dump_len added to allow customizing dump buffer size.
- scx_bpf_exit() added.
- Common headers updated to provide backward compatibility in a way which
hides most complexities from scheduler implementations.
scx_simple, qmap, central and flatcg are updated accordingly. Other
schedulers are broken for the moment.
When a task runs more than once (running <->stopping) within one
runnable-quiescent transition, accumulate runtime of multiple runnings
for statistics. This helps to get the task's runtime per schedule when
supposing that a huge time slice is given, which is what we want to
collect for scheduling decisions.
Signed-off-by: Changwoo Min <changwoo@igalia.com>
Remove runtime_boost using slice_boost_prio. Without slice_boost_prio,
the scheduler collects the exact time slice.
Signed-off-by: Changwoo Min <changwoo@igalia.com>
Let's change the function names of update_stat_for_*() as follow their
callers for consistency and less confusion.
Signed-off-by: Changwoo Min <changwoo@igalia.com>
