All lbmethods are now ind submodules... (6d284302) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP Apache Httpd

modules/proxy/Makefile.in

+1 −1

Original line number	Diff line number	Diff line
		# a modules Makefile has no explicit targets -- they will be defined by
		# whatever modules are enabled. just grab special.mk to deal with this.
		#SUBDIRS = balancers
		SUBDIRS = balancers
		include $(top_srcdir)/build/special.mk

modules/proxy/mod_proxy_balancer.c

+0 −307

Original line number	Diff line number	Diff line
		@@ -941,310 +941,6 @@ static void child_init(apr_pool_t p, server_rec s)

		}

		/*
		* The idea behind the find_best_byrequests scheduler is the following:
		*
		* lbfactor is "how much we expect this worker to work", or "the worker's
		* normalized work quota".
		*
		* lbstatus is "how urgent this worker has to work to fulfill its quota
		* of work".
		*
		* We distribute each worker's work quota to the worker, and then look
		* which of them needs to work most urgently (biggest lbstatus). This
		* worker is then selected for work, and its lbstatus reduced by the
		* total work quota we distributed to all workers. Thus the sum of all
		* lbstatus does not change.(*)
		*
		* If some workers are disabled, the others will
		* still be scheduled correctly.
		*
		* If a balancer is configured as follows:
		*
		* worker a b c d
		* lbfactor 25 25 25 25
		*
		* And b gets disabled, the following schedule is produced:
		*
		* a c d a c d a c d ...
		*
		* Note that the above lbfactor setting is the exact same as:
		*
		* worker a b c d
		* lbfactor 1 1 1 1
		*
		* Asymmetric configurations work as one would expect. For
		* example:
		*
		* worker a b c d
		* lbfactor 1 1 1 2
		*
		* would have a, b and c all handling about the same
		* amount of load with d handling twice what a or b
		* or c handles individually. So we could see:
		*
		* b a d c d a c d b d ...
		*
		*/

		static proxy_worker find_best_byrequests(proxy_balancer balancer,
		request_rec *r)
		{
		int i;
		int total_factor = 0;
		proxy_worker *worker;
		proxy_worker *mycandidate = NULL;
		int cur_lbset = 0;
		int max_lbset = 0;
		int checking_standby;
		int checked_standby;

		ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
		"proxy: Entering byrequests for BALANCER (%s)",
		balancer->name);

		/* First try to see if we have available candidate */
		do {
		checking_standby = checked_standby = 0;
		while (!mycandidate && !checked_standby) {
		worker = (proxy_worker *)balancer->workers->elts;
		for (i = 0; i < balancer->workers->nelts; i++, worker++) {
		if (!checking_standby) { /* first time through */
		if (worker->s->lbset > max_lbset)
		max_lbset = worker->s->lbset;
		}
		if (worker->s->lbset > cur_lbset)
		continue;
		if ( (checking_standby ? !PROXY_WORKER_IS_STANDBY(worker) : PROXY_WORKER_IS_STANDBY(worker)) )
		continue;
		/* If the worker is in error state run
		* retry on that worker. It will be marked as
		* operational if the retry timeout is elapsed.
		* The worker might still be unusable, but we try
		* anyway.
		*/
		if (!PROXY_WORKER_IS_USABLE(worker))
		ap_proxy_retry_worker("BALANCER", worker, r->server);
		/* Take into calculation only the workers that are
		* not in error state or not disabled.
		*/
		if (PROXY_WORKER_IS_USABLE(worker)) {
		worker->s->lbstatus += worker->s->lbfactor;
		total_factor += worker->s->lbfactor;
		if (!mycandidate \|\| worker->s->lbstatus > mycandidate->s->lbstatus)
		mycandidate = worker;
		}
		}
		checked_standby = checking_standby++;
		}
		cur_lbset++;
		} while (cur_lbset <= max_lbset && !mycandidate);

		if (mycandidate) {
		mycandidate->s->lbstatus -= total_factor;
		ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
		"proxy: byrequests selected worker \"%s\" : busy %" APR_SIZE_T_FMT " : lbstatus %d",
		mycandidate->name, mycandidate->s->busy, mycandidate->s->lbstatus);

		}

		return mycandidate;
		}

		/*
		* The idea behind the find_best_bytraffic scheduler is the following:
		*
		* We know the amount of traffic (bytes in and out) handled by each
		* worker. We normalize that traffic by each workers' weight. So assuming
		* a setup as below:
		*
		* worker a b c
		* lbfactor 1 1 3
		*
		* the scheduler will allow worker c to handle 3 times the
		* traffic of a and b. If each request/response results in the
		* same amount of traffic, then c would be accessed 3 times as
		* often as a or b. If, for example, a handled a request that
		* resulted in a large i/o bytecount, then b and c would be
		* chosen more often, to even things out.
		*/
		static proxy_worker find_best_bytraffic(proxy_balancer balancer,
		request_rec *r)
		{
		int i;
		apr_off_t mytraffic = 0;
		apr_off_t curmin = 0;
		proxy_worker *worker;
		proxy_worker *mycandidate = NULL;
		int cur_lbset = 0;
		int max_lbset = 0;
		int checking_standby;
		int checked_standby;

		ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
		"proxy: Entering bytraffic for BALANCER (%s)",
		balancer->name);

		/* First try to see if we have available candidate */
		do {
		checking_standby = checked_standby = 0;
		while (!mycandidate && !checked_standby) {
		worker = (proxy_worker *)balancer->workers->elts;
		for (i = 0; i < balancer->workers->nelts; i++, worker++) {
		if (!checking_standby) { /* first time through */
		if (worker->s->lbset > max_lbset)
		max_lbset = worker->s->lbset;
		}
		if (worker->s->lbset > cur_lbset)
		continue;
		if ( (checking_standby ? !PROXY_WORKER_IS_STANDBY(worker) : PROXY_WORKER_IS_STANDBY(worker)) )
		continue;
		/* If the worker is in error state run
		* retry on that worker. It will be marked as
		* operational if the retry timeout is elapsed.
		* The worker might still be unusable, but we try
		* anyway.
		*/
		if (!PROXY_WORKER_IS_USABLE(worker))
		ap_proxy_retry_worker("BALANCER", worker, r->server);
		/* Take into calculation only the workers that are
		* not in error state or not disabled.
		*/
		if (PROXY_WORKER_IS_USABLE(worker)) {
		mytraffic = (worker->s->transferred/worker->s->lbfactor) +
		(worker->s->read/worker->s->lbfactor);
		if (!mycandidate \|\| mytraffic < curmin) {
		mycandidate = worker;
		curmin = mytraffic;
		}
		}
		}
		checked_standby = checking_standby++;
		}
		cur_lbset++;
		} while (cur_lbset <= max_lbset && !mycandidate);

		if (mycandidate) {
		ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
		"proxy: bytraffic selected worker \"%s\" : busy %" APR_SIZE_T_FMT,
		mycandidate->name, mycandidate->s->busy);

		}

		return mycandidate;
		}

		static proxy_worker find_best_bybusyness(proxy_balancer balancer,
		request_rec *r)
		{

		int i;
		proxy_worker *worker;
		proxy_worker *mycandidate = NULL;
		int cur_lbset = 0;
		int max_lbset = 0;
		int checking_standby;
		int checked_standby;

		int total_factor = 0;

		ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
		"proxy: Entering bybusyness for BALANCER (%s)",
		balancer->name);

		/* First try to see if we have available candidate */
		do {

		checking_standby = checked_standby = 0;
		while (!mycandidate && !checked_standby) {

		worker = (proxy_worker *)balancer->workers->elts;
		for (i = 0; i < balancer->workers->nelts; i++, worker++) {
		if (!checking_standby) { /* first time through */
		if (worker->s->lbset > max_lbset)
		max_lbset = worker->s->lbset;
		}

		if (worker->s->lbset > cur_lbset)
		continue;

		if ( (checking_standby ? !PROXY_WORKER_IS_STANDBY(worker) : PROXY_WORKER_IS_STANDBY(worker)) )
		continue;

		/* If the worker is in error state run
		* retry on that worker. It will be marked as
		* operational if the retry timeout is elapsed.
		* The worker might still be unusable, but we try
		* anyway.
		*/
		if (!PROXY_WORKER_IS_USABLE(worker))
		ap_proxy_retry_worker("BALANCER", worker, r->server);

		/* Take into calculation only the workers that are
		* not in error state or not disabled.
		*/
		if (PROXY_WORKER_IS_USABLE(worker)) {

		worker->s->lbstatus += worker->s->lbfactor;
		total_factor += worker->s->lbfactor;

		if (!mycandidate
		\|\| worker->s->busy < mycandidate->s->busy
		\|\| (worker->s->busy == mycandidate->s->busy && worker->s->lbstatus > mycandidate->s->lbstatus))
		mycandidate = worker;

		}

		}

		checked_standby = checking_standby++;

		}

		cur_lbset++;

		} while (cur_lbset <= max_lbset && !mycandidate);

		if (mycandidate) {
		mycandidate->s->lbstatus -= total_factor;
		ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
		"proxy: bybusyness selected worker \"%s\" : busy %" APR_SIZE_T_FMT " : lbstatus %d",
		mycandidate->name, mycandidate->s->busy, mycandidate->s->lbstatus);

		}

		return mycandidate;

		}

		/*
		* How to add additional lbmethods:
		* 1. Create func which determines "best" candidate worker
		* (eg: find_best_bytraffic, above)
		* 2. Register it as a provider.
		*/
		static const proxy_balancer_method byrequests =
		{
		"byrequests",
		&find_best_byrequests,
		NULL
		};

		static const proxy_balancer_method bytraffic =
		{
		"bytraffic",
		&find_best_bytraffic,
		NULL
		};

		static const proxy_balancer_method bybusyness =
		{
		"bybusyness",
		&find_best_bybusyness,
		NULL
		};


		static void ap_proxy_balancer_register_hook(apr_pool_t *p)
		{
		/* Only the mpm_winnt has child init hook handler.
		@@ -1259,9 +955,6 @@ static void ap_proxy_balancer_register_hook(apr_pool_t *p)
		proxy_hook_pre_request(proxy_balancer_pre_request, NULL, NULL, APR_HOOK_FIRST);
		proxy_hook_post_request(proxy_balancer_post_request, NULL, NULL, APR_HOOK_FIRST);
		proxy_hook_canon_handler(proxy_balancer_canon, NULL, NULL, APR_HOOK_FIRST);
		ap_register_provider(p, PROXY_LBMETHOD, "bytraffic", "0", &bytraffic);
		ap_register_provider(p, PROXY_LBMETHOD, "byrequests", "0", &byrequests);
		ap_register_provider(p, PROXY_LBMETHOD, "bybusyness", "0", &bybusyness);
		}

		module AP_MODULE_DECLARE_DATA proxy_balancer_module = {