Commit 97c5373f authored by Maciej Szwed's avatar Maciej Szwed Committed by Ben Walker
Browse files

test/scheduler: make activity of a thread % of time period 



So far the test application was mostly used for cases with
single active thread on a core.
Setting activity as percentage of all poller operations worked
fine for those cases.

This patch changes the thread activity to mean percentage of
a set time period.
Which equals to the maximum load a thread will see when being
alone on the core.

Right now g_core_time_period is set to 100ms, and is the
maximum execution time for all threads on a core when
thread activity is set to 100%.
g_timeslice is set to 100us and is the execution time of
single thread poll.

Consider following scenario:

Before the patch
Thread1	Activity 70%	Busy 70		Idle 30	Load 70%
Thread2	Activity 60%	Busy 60		Idle 40	Load 60%
Core			Busy 130	Idle 70	Load 65%

After the patch
Thread1	Activity 70%	Busy 100	Idle 0	Load 100%
Thread2	Activity 60%	Busy 100	Idle 0	Load 100%
Core			Busy 200	Idle 0	Load 100%

Additionally increased period of sleeping from 1us to 100us,
to offset the time needed for additional operations
during thread poll.

Signed-off-by: default avatarTomasz Zawadzki <tomasz.zawadzki@intel.com>
Signed-off-by: default avatarMaciej Szwed <maciej.szwed@intel.com>
Change-Id: I027432db1bea570dd58829eeccf7dd8bb06bf249
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/7474


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Reviewed-by: default avatarPaul Luse <paul.e.luse@intel.com>
Reviewed-by: default avatarKrzysztof Karas <krzysztof.karas@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
parent 11c9b396

test/event/scheduler/scheduler.c

+24 −5
Original line number Diff line number Diff line
@@ -45,11 +45,16 @@ 


static bool g_is_running = true;

pthread_mutex_t g_sched_list_mutex = PTHREAD_MUTEX_INITIALIZER;

#define TIMESLICE_US 100 /* Execution time of single busy thread poll in us. */

static uint64_t g_core_time_period;

static uint64_t g_timeslice_tsc;



struct sched_thread {

	struct spdk_thread *thread;

	struct spdk_poller *poller;

	int active_percent;

	uint64_t next_period_tsc;

	uint64_t remaining_tsc;

	struct spdk_jsonrpc_request *request;

	TAILQ_ENTRY(sched_thread) link;

};
@@ -99,12 +104,11 @@ thread_delete(struct sched_thread *sched_thread) 
	}

}



static __thread unsigned int seed = 0;



static int

poller_run(void *arg)

{

	struct sched_thread *sched_thread = arg;

	uint64_t now;



	if (spdk_unlikely(!g_is_running)) {

		pthread_mutex_lock(&g_sched_list_mutex);
@@ -113,10 +117,17 @@ poller_run(void *arg) 
		return SPDK_POLLER_IDLE;

	}



	spdk_delay_us(1);

	now = spdk_get_ticks();



	/* Reset the timers once we go over single core time period */

	if (sched_thread->next_period_tsc <= now) {

		sched_thread->next_period_tsc = now + g_core_time_period;

		sched_thread->remaining_tsc = (g_core_time_period / 100) * sched_thread->active_percent;

	}



	if ((sched_thread->active_percent == 100) ||

	    (sched_thread->active_percent != 0 && (rand_r(&seed) % 100) < sched_thread->active_percent)) {

	if (sched_thread->remaining_tsc > 0) {

		spdk_delay_us(TIMESLICE_US);

		sched_thread->remaining_tsc -= spdk_min(sched_thread->remaining_tsc, g_timeslice_tsc);

		return SPDK_POLLER_BUSY;

	}
@@ -184,6 +195,7 @@ rpc_scheduler_thread_create(struct spdk_jsonrpc_request *request, 


	sched_thread->request = request;

	sched_thread->active_percent = req.active_percent;

	sched_thread->next_period_tsc = 0;



	spdk_thread_send_msg(sched_thread->thread, rpc_register_poller, sched_thread);
@@ -225,6 +237,8 @@ rpc_scheduler_thread_set_active_cb(void *arg) 
	pthread_mutex_lock(&g_sched_list_mutex);

	TAILQ_FOREACH(sched_thread, &g_sched_threads, link) {

		if (spdk_thread_get_id(sched_thread->thread) == thread_id) {

			/* Reset next_period_tsc to force recalculation of remaining_tsc. */

			sched_thread->next_period_tsc = 0;

			sched_thread->active_percent = ctx->active_percent;

			pthread_mutex_unlock(&g_sched_list_mutex);

			spdk_jsonrpc_send_bool_response(ctx->request, true);
@@ -367,6 +381,11 @@ test_shutdown(void) 
static void

test_start(void *arg1)

{

	/* Hardcode g_core_time_period as 100ms. */

	g_core_time_period = spdk_get_ticks_hz() / 10;

	/* Hardcode g_timeslice_tsc as 100us. */

	g_timeslice_tsc = spdk_get_ticks_hz() / SPDK_SEC_TO_USEC * TIMESLICE_US;



	SPDK_NOTICELOG("Scheduler test application started.\n");

}