Commit 1a5f26a4 authored by Brian Pane's avatar Brian Pane
Browse files

Added caching of formatted timestamps to speed up the access logger when 

using standard time format


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@95046 13f79535-47bb-0310-9956-ffa450edef68
parent 2a2a9b81

CHANGES

+3 −0
Changes for CHANGES: 3 added lines, 0 removed lines.
Original line number Diff line number Diff line 
Changes with Apache 2.0.37









  *) Performance enhancements for access logger when using









     default timestamp formatting  [Brian Pane]

















  *) Added EnableMMAP config directive to enable the server









     administrator to disable memory-mapping of delivered files









     on a per-directory basis.  [Brian Pane]


































modules/loggers/mod_log_config.c



+47
−9



























Changes for modules/loggers/mod_log_config.c: 47 added lines, 9 removed lines.



Original line number
Diff line number
Diff line







@@ -455,6 +455,17 @@ static const char *log_request_time_custom(request_rec *r, char *a,







    return apr_pstrdup(r->pool, tstr);









}



















#define DEFAULT_REQUEST_TIME_SIZE 32









typedef struct {









    apr_int64_t t;









    char timestr[DEFAULT_REQUEST_TIME_SIZE];









    apr_int64_t t_validate;









} cached_request_time;



















#define TIME_CACHE_SIZE 4









#define TIME_CACHE_MASK 3









static cached_request_time request_time_cache[TIME_CACHE_SIZE];



















static const char *log_request_time(request_rec *r, char *a)









{









    apr_time_exp_t xt;










@@ -470,11 +481,6 @@ static const char *log_request_time(request_rec *r, char *a)







	than force the server to pay extra cpu cycles.	if you've got









	a problem with this, you can set the define.  -djg









    */









#ifdef I_INSIST_ON_EXTRA_CYCLES_FOR_CLF_COMPLIANCE









    ap_explode_recent_localtime(&xt, apr_time_now());









#else









    ap_explode_recent_localtime(&xt, r->request_time);









#endif









    if (a && *a) {              /* Custom format */









        /* The custom time formatting uses a very large temp buffer









         * on the stack.  To avoid using so much stack space in the










@@ -482,12 +488,38 @@ static const char *log_request_time(request_rec *r, char *a)







         * for the custom format in a separate function.  (That's why









         * log_request_time_custom is not inlined right here.)









         */









#ifdef I_INSIST_ON_EXTRA_CYCLES_FOR_CLF_COMPLIANCE









        ap_explode_recent_localtime(&xt, apr_time_now());









#else









        ap_explode_recent_localtime(&xt, r->request_time);









#endif









        return log_request_time_custom(r, a, &xt);









    }









    else {                      /* CLF format */









        /* This code uses the same technique as ap_explode_recent_localtime():









         * optimistic caching with logic to detect and correct race conditions.









         * See the comments in server/util_time.c for more information.









         */









        cached_request_time* cached_time = apr_palloc(r->pool,









                                                      sizeof(*cached_time));









#ifdef I_INSIST_ON_EXTRA_CYCLES_FOR_CLF_COMPLIANCE









        apr_time_t request_time = apr_time_now();









#else









        apr_time_t request_time = r->request_time;









#endif









        unsigned i = request_time / APR_USEC_PER_SEC;









        i &= TIME_CACHE_MASK;









        memcpy(cached_time, &(request_time_cache[i]), sizeof(*cached_time));









        if ((request_time != cached_time->t) ||









            (request_time != cached_time->t_validate)) {



















            /* Invalid or old snapshot, so compute the proper time string









             * and store it in the cache









             */









            char sign;









            int timz;



















            ap_explode_recent_localtime(&xt, r->request_time);









            timz = xt.tm_gmtoff;









            if (timz < 0) {









                timz = -timz;










@@ -496,11 +528,17 @@ static const char *log_request_time(request_rec *r, char *a)







            else {









                sign = '+';









            }



















        return apr_psprintf(r->pool, "[%02d/%s/%d:%02d:%02d:%02d %c%.2d%.2d]",









                xt.tm_mday, apr_month_snames[xt.tm_mon], xt.tm_year+1900,









                xt.tm_hour, xt.tm_min, xt.tm_sec,









            cached_time->t = request_time;









            apr_snprintf(cached_time->timestr, DEFAULT_REQUEST_TIME_SIZE,









                         "[%02d/%s/%d:%02d:%02d:%02d %c%.2d%.2d]",









                         xt.tm_mday, apr_month_snames[xt.tm_mon],









                         xt.tm_year+1900, xt.tm_hour, xt.tm_min, xt.tm_sec,









                         sign, timz / (60*60), timz % (60*60));









            cached_time->t_validate = request_time;









            memcpy(&(request_time_cache[i]), cached_time,









                   sizeof(*cached_time));









        }









        return cached_time->timestr;









    }









}