httpd/include/scoreboard.h

	scoreboard.h revision ce03576b2434cec77f2921db9d5b6a0510581c23
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder/* ====================================================================
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * The Apache Software License, Version 1.1
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * Copyright (c) 2000-2001 The Apache Software Foundation.  All rights
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * reserved.
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * Redistribution and use in source and binary forms, with or without
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * modification, are permitted provided that the following conditions
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * are met:
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * 1. Redistributions of source code must retain the above copyright
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *    notice, this list of conditions and the following disclaimer.
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * 2. Redistributions in binary form must reproduce the above copyright
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *    notice, this list of conditions and the following disclaimer in
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder *    the documentation and/or other materials provided with the
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder *    distribution.
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * 3. The end-user documentation included with the redistribution,
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *    if any, must include the following acknowledgment:
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *       "This product includes software developed by the
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *        Apache Software Foundation (http://www.apache.org/)."
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *    Alternately, this acknowledgment may appear in the software itself,
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder *    if and wherever such third-party acknowledgments normally appear.
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder *
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * 4. The names "Apache" and "Apache Software Foundation" must
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder *    not be used to endorse or promote products derived from this
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder *    software without prior written permission. For written
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder *    permission, please contact apache@apache.org.
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder *
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * 5. Products derived from this software may not be called "Apache",
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder *    nor may "Apache" appear in their name, without prior written
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder *    permission of the Apache Software Foundation.
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder *
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * SUCH DAMAGE.
06f58a67e6df999858bf4f97d5e0786956562d29Christian Maeder * ====================================================================
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder *
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * This software consists of voluntary contributions made by many
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * individuals on behalf of the Apache Software Foundation.  For more
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * information on the Apache Software Foundation, please see
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * <http://www.apache.org/>.
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder *
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder * Portions of this software are based upon public domain software
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder * originally written at the National Center for Supercomputing Applications,
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder * University of Illinois, Urbana-Champaign.
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder */
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder#ifndef APACHE_SCOREBOARD_H
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder#define APACHE_SCOREBOARD_H
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder#ifdef __cplusplus
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maederextern "C" {
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#endif
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder#ifdef HAVE_SYS_TIMES_H
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#include <sys/time.h>
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#include <sys/times.h>
bb2c1beb7ab66a49627a2a34df80864a3c65cc83Christian Maeder#elif defined(TPF)
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#include <time.h>
bb2c1beb7ab66a49627a2a34df80864a3c65cc83Christian Maeder#endif
bb2c1beb7ab66a49627a2a34df80864a3c65cc83Christian Maeder
bb2c1beb7ab66a49627a2a34df80864a3c65cc83Christian Maeder#include "mpm_default.h"    /* For HARD_.*_LIMIT */
bb2c1beb7ab66a49627a2a34df80864a3c65cc83Christian Maeder#include "apr_thread_proc.h"
bb2c1beb7ab66a49627a2a34df80864a3c65cc83Christian Maeder#include "apr_portable.h"
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder/* The optimized timeouts only work if we're not using a scoreboard file */
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#if !APR_FILE_BASED_SHM
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#define OPTIMIZE_TIMEOUTS
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#endif
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder/* Scoreboard info on a process is, for now, kept very brief ---
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * just status value and pid (the latter so that the caretaker process
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * can properly update the scoreboard when a process dies).  We may want
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * to eventually add a separate set of long_score structures which would
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * give, for each process, the number of requests serviced, and info on
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * the current, or most recent, request.
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder *
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * Status values:
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder */
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder#define SERVER_DEAD 0
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder#define SERVER_STARTING 1   /* Server Starting up */
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder#define SERVER_READY 2      /* Waiting for connection (or accept() lock) */
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#define SERVER_BUSY_READ 3  /* Reading a client request */
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder#define SERVER_BUSY_WRITE 4 /* Processing a client request */
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder#define SERVER_BUSY_KEEPALIVE 5 /* Waiting for more requests via keepalive */
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder#define SERVER_BUSY_LOG 6   /* Logging the request */
d4aed7a2eea6b546c0d9520d85038addb7beb12fChristian Maeder#define SERVER_BUSY_DNS 7   /* Looking up a hostname */
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder#define SERVER_GRACEFUL 8   /* server is gracefully finishing request */
38824a7dba4f7d82532afec67e0b594a5af5d76bChristian Maeder#define SERVER_ACCEPTING 9  /* thread is accepting connections */
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#define SERVER_QUEUEING 10      /* thread is putting connection on the queue */
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#define SERVER_IDLE_KILL 11     /* Server is cleaning up idle children. */
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder#define SERVER_NUM_STATUS 12    /* number of status settings */
a1a48072301767054f2a9ff7ccf8974b0d6a6a28Christian Maeder
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder/* A "virtual time" is simply a counter that indicates that a child is
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * making progress.  The parent checks up on each child, and when they have
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * made progress it resets the last_rtime element.  But when the child hasn't
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * made progress in a time that's roughly timeout_len seconds long, it is
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * sent a SIGALRM.
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder *
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * vtime is an optimization that is used only when the scoreboard is in
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * shared memory (it's not easy/feasible to do it in a scoreboard file).
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * The essential observation is that timeouts rarely occur, the vast majority
5b3e0bbb6a776c60dc14113435a44e7b13d2fa01Christian Maeder * of hits finish before any timeout happens.  So it really sucks to have to
36a493b7eec0f9d719674296c26afe7fd9bfe327Christian Maeder * ask the operating system to set up and destroy alarms many times during
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * a request.
7fe976d9f9c4af1aa7636c568d9919859523de0aChristian Maeder */
38f35f2c4a3b6a778f4f68e7af047a174e93abbeChristian Maedertypedef unsigned vtime_t;
38f35f2c4a3b6a778f4f68e7af047a174e93abbeChristian Maeder
13140d161d2d2d11d87283d01d57ee3a738a833dChristian Maeder/* Type used for generation indicies.  Startup and every restart cause a
38f35f2c4a3b6a778f4f68e7af047a174e93abbeChristian Maeder * new generation of children to be spawned.  Children within the same
38f35f2c4a3b6a778f4f68e7af047a174e93abbeChristian Maeder * generation share the same configuration information -- pointers to stuff
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * created at config time in the parent are valid across children.  For
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * example, the vhostrec pointer in the scoreboard below is valid in all
38f35f2c4a3b6a778f4f68e7af047a174e93abbeChristian Maeder * children of the same generation.
38f35f2c4a3b6a778f4f68e7af047a174e93abbeChristian Maeder *
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder * The safe way to access the vhost pointer is like this:
38f35f2c4a3b6a778f4f68e7af047a174e93abbeChristian Maeder *
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * short_score *ss = pointer to whichver slot is interesting;
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * parent_score *ps = pointer to whichver slot is interesting;
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * server_rec *vh = ss->vhostrec;
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder *
13140d161d2d2d11d87283d01d57ee3a738a833dChristian Maeder * if (ps->generation != ap_my_generation) {
13140d161d2d2d11d87283d01d57ee3a738a833dChristian Maeder *     vh = NULL;
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder * }
13140d161d2d2d11d87283d01d57ee3a738a833dChristian Maeder *
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * then if vh is not NULL it's valid in this child.
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder *
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder * This avoids various race conditions around restarts.
0c92a39a4adf3c1cbe173e3b16c65c159a1ce612Christian Maeder */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maedertypedef int ap_generation_t;
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder/* Is the scoreboard shared between processes or not?
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder * Set by the MPM when the scoreboard is created.
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maedertypedef enum {
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder    SB_SHARED = 1,
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder    SB_NOT_SHARED = 2
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder} ap_scoreboard_e;
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder#define SB_WORKING  0  /* The server is busy and the child is useful. */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder#define SB_IDLE_DIE 1  /* The server is idle and the child is superfluous. */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder                       /*   The child should check for this and exit gracefully. */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder/* stuff which is thread/process specific */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maedertypedef struct {
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder#ifdef OPTIMIZE_TIMEOUTS
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder    vtime_t cur_vtime;      /* the child's current vtime */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder    unsigned short timeout_len; /* length of the timeout */
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder#endif
05b9abe2e7d9e6126bf4ae29be6ef3693f32de73Christian Maeder    int thread_num;
#if APR_HAS_THREADS
    apr_os_thread_t tid;
#endif
    unsigned char status;
    unsigned long access_count;
    unsigned long bytes_served;
    unsigned long my_access_count;
    unsigned long my_bytes_served;
    unsigned long conn_bytes;
    unsigned short conn_count;
    unsigned short life_status;    /* Either SB_WORKING or SB_IDLE_DIE */
    apr_time_t start_time;
    apr_time_t stop_time;
#ifdef HAVE_TIMES
    struct tms times;
#endif
#ifndef OPTIMIZE_TIMEOUTS
    time_t last_used;
#endif
    char client[32];        /* Keep 'em small... */
    char request[64];       /* We just want an idea... */
    server_rec *vhostrec;   /* What virtual host is being accessed? */
                                /* SEE ABOVE FOR SAFE USAGE! */
} short_score;

typedef struct {
    ap_scoreboard_e sb_type;
    ap_generation_t running_generation; /* the generation of children which
                                         * should still be serving requests. */
} global_score;

/* stuff which the parent generally writes and the children rarely read */
typedef struct {
    pid_t pid;
    ap_generation_t generation; /* generation of this child */
    int worker_threads;
#ifdef OPTIMIZE_TIMEOUTS
    time_t last_rtime;      /* time(0) of the last change */
    vtime_t last_vtime;     /* the last vtime the parent has seen */
#endif
} parent_score;

typedef struct {
    short_score servers[HARD_SERVER_LIMIT][HARD_THREAD_LIMIT];
    parent_score parent[HARD_SERVER_LIMIT];
    global_score global;
} scoreboard;

#define KEY_LENGTH 16
#define VALUE_LENGTH 64
typedef struct {
    char key[KEY_LENGTH];
    char value[VALUE_LENGTH];
} status_table_entry;

#define STATUSES_PER_CONNECTION 10

typedef struct {
    status_table_entry
        table[HARD_SERVER_LIMIT*HARD_THREAD_LIMIT][STATUSES_PER_CONNECTION];
} new_scoreboard;

#define SCOREBOARD_SIZE     sizeof(scoreboard)
#define NEW_SCOREBOARD_SIZE sizeof(new_scoreboard)
#ifdef TPF
#define SCOREBOARD_NAME     "SCOREBRD"
#define SCOREBOARD_FRAMES       SCOREBOARD_SIZE/4095 + 1
#endif

AP_DECLARE(int) ap_exists_scoreboard_image(void);
AP_DECLARE(void) ap_create_scoreboard(apr_pool_t *p, ap_scoreboard_e t);
AP_DECLARE(void) ap_increment_counts(int child_num, int thread_num, request_rec *r);

apr_status_t ap_cleanup_scoreboard(void *d);

AP_DECLARE(void) reopen_scoreboard(apr_pool_t *p);

void ap_sync_scoreboard_image(void);

void update_scoreboard_global(void);
AP_DECLARE(int) find_child_by_pid(apr_proc_t *pid);
int ap_update_child_status(int child_num, int thread_num, int status, request_rec *r);
void ap_time_process_request(int child_num, int thread_num, int status);


AP_DECLARE_DATA extern scoreboard *ap_scoreboard_image;
AP_DECLARE_DATA extern const char *ap_scoreboard_fname;
AP_DECLARE_DATA extern int ap_extended_status;
AP_DECLARE_DATA extern apr_time_t ap_restart_time;

AP_DECLARE_DATA extern ap_generation_t volatile ap_my_generation;

/* for time_process_request() in http_main.c */
#define START_PREQUEST 1
#define STOP_PREQUEST  2

#ifdef __cplusplus
}
#endif

#endif  /* !APACHE_SCOREBOARD_H */