darshan-core.c 51.2 KB
Newer Older
1
/*
Shane Snyder's avatar
Shane Snyder committed
2 3 4
 * Copyright (C) 2015 University of Chicago.
 * See COPYRIGHT notice in top-level directory.
 *
5 6
 */

7
#define _XOPEN_SOURCE 500
8
#define _GNU_SOURCE
9

10 11 12 13 14 15
#include "darshan-runtime-config.h"

#include <stdio.h>
#ifdef HAVE_MNTENT_H
#include <mntent.h>
#endif
16 17 18 19 20
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <limits.h>
#include <pthread.h>
21 22 23
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/vfs.h>
24
#include <zlib.h>
25
#include <mpi.h>
26
#include <assert.h>
27

28
#include "uthash.h"
Shane Snyder's avatar
Shane Snyder committed
29
#include "darshan.h"
30
#include "darshan-core.h"
Shane Snyder's avatar
Shane Snyder committed
31
#include "darshan-dynamic.h"
32

33
extern char* __progname;
34
extern char* __progname_full;
35

36
/* internal variable delcarations */
37
static struct darshan_core_runtime *darshan_core = NULL;
38
static pthread_mutex_t darshan_core_mutex = PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
39
static int my_rank = -1;
40
static int nprocs = -1;
41
static int darshan_mem_alignment = 1;
42

43 44 45 46 47 48 49 50 51 52 53 54 55 56 57
/* paths prefixed with the following directories are not traced by darshan */
char* darshan_path_exclusions[] = {
"/etc/",
"/dev/",
"/usr/",
"/bin/",
"/boot/",
"/lib/",
"/opt/",
"/sbin/",
"/sys/",
"/proc/",
NULL
};

58 59 60 61 62 63 64 65 66 67 68 69 70 71 72
#ifdef DARSHAN_BGQ
extern void bgq_runtime_initialize();
#endif

/* array of init functions for modules which need to be statically
 * initialized by darshan at startup time
 */
void (*mod_static_init_fns[])(void) =
{
#ifdef DARSHAN_BGQ
    &bgq_runtime_initialize,
#endif
    NULL
};

Shane Snyder's avatar
Shane Snyder committed
73 74 75
#define DARSHAN_CORE_LOCK() pthread_mutex_lock(&darshan_core_mutex)
#define DARSHAN_CORE_UNLOCK() pthread_mutex_unlock(&darshan_core_mutex)

76 77 78 79 80 81
/* FS mount information */
#define DARSHAN_MAX_MNTS 64
#define DARSHAN_MAX_MNT_PATH 256
#define DARSHAN_MAX_MNT_TYPE 32
struct mnt_data
{
82
    int block_size;
83 84 85 86 87 88
    char path[DARSHAN_MAX_MNT_PATH];
    char type[DARSHAN_MAX_MNT_TYPE];
};
static struct mnt_data mnt_data_array[DARSHAN_MAX_MNTS];
static int mnt_data_count = 0;

89 90 91 92
/* prototypes for internal helper functions */
static void darshan_get_logfile_name(
    char* logfile_name, int jobid, struct tm* start_tm);
static void darshan_log_record_hints_and_ver(
93 94 95 96 97 98
    struct darshan_core_runtime* core);
static void darshan_get_exe_and_mounts_root(
    struct darshan_core_runtime *core, char* trailing_data,
    int space_left);
static char* darshan_get_exe_and_mounts(
    struct darshan_core_runtime *core);
99 100
static void darshan_block_size_from_path(
    const char *path, int *block_size);
101
static void darshan_get_shared_records(
102 103
    struct darshan_core_runtime *core, darshan_record_id **shared_recs,
    int *shared_rec_cnt);
104
static int darshan_log_open_all(
105
    char *logfile_name, MPI_File *log_fh);
106
static int darshan_deflate_buffer(
Shane Snyder's avatar
Shane Snyder committed
107 108
    void **pointers, int *lengths, int count, char *comp_buf,
    int *comp_buf_length);
109
static int darshan_log_write_record_hash(
110
    MPI_File log_fh, struct darshan_core_runtime *core,
111 112 113
    uint64_t *inout_off);
static int darshan_log_append_all(
    MPI_File log_fh, struct darshan_core_runtime *core, void *buf,
Shane Snyder's avatar
Shane Snyder committed
114
    int count, uint64_t *inout_off);
Shane Snyder's avatar
Shane Snyder committed
115 116
static void darshan_core_cleanup(
    struct darshan_core_runtime* core);
117

118 119
/* *********************************** */

Shane Snyder's avatar
Shane Snyder committed
120
void darshan_core_initialize(int argc, char **argv)
121 122 123 124
{
    int i;
    int internal_timing_flag = 0;
    double init_start, init_time, init_max;
125
    char *envstr;
126 127 128
    char* truncate_string = "<TRUNCATED>";
    int truncate_offset;
    int chars_left = 0;
129 130
    int ret;
    int tmpval;
131 132

    DARSHAN_MPI_CALL(PMPI_Comm_size)(MPI_COMM_WORLD, &nprocs);
133
    DARSHAN_MPI_CALL(PMPI_Comm_rank)(MPI_COMM_WORLD, &my_rank);
134 135 136 137

    if(getenv("DARSHAN_INTERNAL_TIMING"))
        internal_timing_flag = 1;

138
    if(internal_timing_flag)
139 140 141
        init_start = DARSHAN_MPI_CALL(PMPI_Wtime)();

    /* setup darshan runtime if darshan is enabled and hasn't been initialized already */
142
    if(!getenv("DARSHAN_DISABLE") && !darshan_core)
143
    {
144
        #if (__DARSHAN_MEM_ALIGNMENT < 1)
145 146
            #error Darshan must be configured with a positive value for --with-mem-align
        #endif
147
        envstr = getenv(DARSHAN_MEM_ALIGNMENT_OVERRIDE);
148 149 150 151 152 153 154 155 156 157 158
        if(envstr)
        {
            ret = sscanf(envstr, "%d", &tmpval);
            /* silently ignore if the env variable is set poorly */
            if(ret == 1 && tmpval > 0)
            {
                darshan_mem_alignment = tmpval;
            }
        }
        else
        {
159
            darshan_mem_alignment = __DARSHAN_MEM_ALIGNMENT;
160 161 162 163 164 165 166
        }

        /* avoid floating point errors on faulty input */
        if (darshan_mem_alignment < 1)
        {
            darshan_mem_alignment = 1;
        }
167 168 169 170

        /* allocate structure to track darshan_core_runtime information */
        darshan_core = malloc(sizeof(*darshan_core));
        if(darshan_core)
171
        {
172
            memset(darshan_core, 0, sizeof(*darshan_core));
173

174 175 176 177
            darshan_core->log_job.uid = getuid();
            darshan_core->log_job.start_time = time(NULL);
            darshan_core->log_job.nprocs = nprocs;
            darshan_core->wtime_offset = DARSHAN_MPI_CALL(PMPI_Wtime)();
178 179

            /* record exe and arguments */
180
            for(i=0; i<argc; i++)
181
            {
182
                chars_left = DARSHAN_EXE_LEN-strlen(darshan_core->exe);
183 184
                strncat(darshan_core->exe, argv[i], chars_left);
                if(i < (argc-1))
185
                {
186
                    chars_left = DARSHAN_EXE_LEN-strlen(darshan_core->exe);
187
                    strncat(darshan_core->exe, " ", chars_left);
188 189 190 191 192 193 194 195
                }
            }

            /* if we don't see any arguments, then use glibc symbol to get
             * program name at least (this happens in fortran)
             */
            if(argc == 0)
            {
196
                chars_left = DARSHAN_EXE_LEN-strlen(darshan_core->exe);
197
                strncat(darshan_core->exe, __progname_full, chars_left);
198
                chars_left = DARSHAN_EXE_LEN-strlen(darshan_core->exe);
199
                strncat(darshan_core->exe, " <unknown args>", chars_left);
200 201 202 203 204
            }

            if(chars_left == 0)
            {
                /* we ran out of room; mark that string was truncated */
205
                truncate_offset = DARSHAN_EXE_LEN - strlen(truncate_string);
206
                sprintf(&darshan_core->exe[truncate_offset], "%s",
207 208
                    truncate_string);
            }
209 210 211

            /* collect information about command line and mounted file systems */
            darshan_core->trailing_data = darshan_get_exe_and_mounts(darshan_core);
212

Shane Snyder's avatar
Shane Snyder committed
213 214 215 216 217 218 219
            /* bootstrap any modules with static initialization routines */
            i = 0;
            while(mod_static_init_fns[i])
            {
                (*mod_static_init_fns[i])();
                i++;
            }
220
        }
221 222
    }

223 224 225 226 227
    if(internal_timing_flag)
    {
        init_time = DARSHAN_MPI_CALL(PMPI_Wtime)() - init_start;
        DARSHAN_MPI_CALL(PMPI_Reduce)(&init_time, &init_max, 1,
            MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
228
        if(my_rank == 0)
229
        {
230 231
            fprintf(stderr, "#darshan:<op>\t<nprocs>\t<time>\n");
            fprintf(stderr, "darshan:init\t%d\t%f\n", nprocs, init_max);
232 233 234 235 236 237
        }
    }

    return;
}

Shane Snyder's avatar
Shane Snyder committed
238
void darshan_core_shutdown()
239
{
240
    int i;
241
    char *logfile_name;
242
    struct darshan_core_runtime *final_core;
243
    int internal_timing_flag = 0;
244 245
    char *envjobid;
    char *jobid_str;
246
    int jobid;
247
    struct tm *start_tm;
248
    time_t start_time_tmp;
249 250
    int ret = 0;
    int all_ret = 0;
251 252
    int64_t first_start_time;
    int64_t last_end_time;
253 254
    int local_mod_use[DARSHAN_MAX_MODS] = {0};
    int global_mod_use_count[DARSHAN_MAX_MODS] = {0};
255 256 257
    darshan_record_id *shared_recs;
    darshan_record_id *mod_shared_recs;
    int shared_rec_cnt = 0;
258
    double start_log_time;
259 260 261 262 263 264 265
    double open1, open2;
    double job1, job2;
    double rec1, rec2;
    double mod1[DARSHAN_MAX_MODS] = {0};
    double mod2[DARSHAN_MAX_MODS] = {0};
    double header1, header2;
    double tm_end;
266
    uint64_t gz_fp = 0;
267 268
    MPI_File log_fh;
    MPI_Status status;
269 270 271 272

    if(getenv("DARSHAN_INTERNAL_TIMING"))
        internal_timing_flag = 1;

273 274
    start_log_time = DARSHAN_MPI_CALL(PMPI_Wtime)();

Shane Snyder's avatar
Shane Snyder committed
275
    /* disable darhan-core while we shutdown */
276
    DARSHAN_CORE_LOCK();
277
    if(!darshan_core)
278
    {
279
        DARSHAN_CORE_UNLOCK();
280 281
        return;
    }
282 283
    final_core = darshan_core;
    darshan_core = NULL;
Shane Snyder's avatar
Shane Snyder committed
284

285
    /* we also need to set which modules were registered on this process and
286 287
     * call into those modules and give them a chance to perform any necessary
     * pre-shutdown steps.
Shane Snyder's avatar
Shane Snyder committed
288 289 290 291 292 293
     */
    for(i = 0; i < DARSHAN_MAX_MODS; i++)
    {
        if(final_core->mod_array[i])
        {
            local_mod_use[i] = 1;
294
            final_core->mod_array[i]->mod_funcs.begin_shutdown();
Shane Snyder's avatar
Shane Snyder committed
295 296
        }
    }
297
    DARSHAN_CORE_UNLOCK();
298 299 300 301

    logfile_name = malloc(PATH_MAX);
    if(!logfile_name)
    {
302
        darshan_core_cleanup(final_core);
303 304 305
        return;
    }

306
    /* set darshan job id/metadata and constuct log file name on rank 0 */
307
    if(my_rank == 0)
308
    {
309
        /* Use DARSHAN_JOBID_OVERRIDE for the env var for __DARSHAN_JOBID */
310
        envjobid = getenv(DARSHAN_JOBID_OVERRIDE);
311
        if(!envjobid)
312
        {
313
            envjobid = __DARSHAN_JOBID;
314 315
        }

316
        /* find a job id */
317 318 319 320 321 322 323 324 325 326 327 328
        jobid_str = getenv(envjobid);
        if(jobid_str)
        {
            /* in cobalt we can find it in env var */
            ret = sscanf(jobid_str, "%d", &jobid);
        }
        if(!jobid_str || ret != 1)
        {
            /* use pid as fall back */
            jobid = getpid();
        }

329
        final_core->log_job.jobid = (int64_t)jobid;
330

331
        /* if we are using any hints to write the log file, then record those
332
         * hints with the darshan job information
333
         */
334
        darshan_log_record_hints_and_ver(final_core);
335

336
        /* use human readable start time format in log filename */
337
        start_time_tmp = final_core->log_job.start_time;
338
        start_tm = localtime(&start_time_tmp);
339

340 341
        /* construct log file name */
        darshan_get_logfile_name(logfile_name, jobid, start_tm);
342 343 344 345 346 347 348 349 350
    }

    /* broadcast log file name */
    DARSHAN_MPI_CALL(PMPI_Bcast)(logfile_name, PATH_MAX, MPI_CHAR, 0,
        MPI_COMM_WORLD);

    if(strlen(logfile_name) == 0)
    {
        /* failed to generate log file name */
351
        free(logfile_name);
352
        darshan_core_cleanup(final_core);
353 354 355
        return;
    }

356
    final_core->log_job.end_time = time(NULL);
357

358 359 360
    /* reduce to report first start time and last end time across all ranks
     * at rank 0
     */
361 362
    DARSHAN_MPI_CALL(PMPI_Reduce)(&final_core->log_job.start_time, &first_start_time, 1, MPI_LONG_LONG, MPI_MIN, 0, MPI_COMM_WORLD);
    DARSHAN_MPI_CALL(PMPI_Reduce)(&final_core->log_job.end_time, &last_end_time, 1, MPI_LONG_LONG, MPI_MAX, 0, MPI_COMM_WORLD);
363 364
    if(my_rank == 0)
    {
365 366
        final_core->log_job.start_time = first_start_time;
        final_core->log_job.end_time = last_end_time;
367
    }
368

369 370 371
    /* reduce the number of times a module was opened globally and bcast to everyone */   
    DARSHAN_MPI_CALL(PMPI_Allreduce)(local_mod_use, global_mod_use_count, DARSHAN_MAX_MODS, MPI_INT, MPI_SUM, MPI_COMM_WORLD);

372
    /* get a list of records which are shared across all processes */
373
    darshan_get_shared_records(final_core, &shared_recs, &shared_rec_cnt);
374

375 376
    if(internal_timing_flag)
        open1 = DARSHAN_MPI_CALL(PMPI_Wtime)();
377
    /* collectively open the darshan log file */
378
    ret = darshan_log_open_all(logfile_name, &log_fh);
379 380
    if(internal_timing_flag)
        open2 = DARSHAN_MPI_CALL(PMPI_Wtime)();
381 382 383 384 385 386 387 388

    /* error out if unable to open log file */
    DARSHAN_MPI_CALL(PMPI_Allreduce)(&ret, &all_ret, 1, MPI_INT,
        MPI_LOR, MPI_COMM_WORLD);
    if(all_ret != 0)
    {
        if(my_rank == 0)
        {
389 390
            fprintf(stderr, "darshan library warning: unable to open log file %s\n",
                logfile_name);
391 392
        }
        free(logfile_name);
393
        darshan_core_cleanup(final_core);
394 395 396
        return;
    }

397 398
    if(internal_timing_flag)
        job1 = DARSHAN_MPI_CALL(PMPI_Wtime)();
399
    /* rank 0 is responsible for writing the compressed darshan job information */
Shane Snyder's avatar
Shane Snyder committed
400
    if(my_rank == 0)
401
    {
402
        void *pointers[2] = {&final_core->log_job, final_core->trailing_data};
403
        int lengths[2] = {sizeof(struct darshan_job), strlen(final_core->trailing_data)};
404
        int comp_buf_sz = 0;
405

406
        /* compress the job info and the trailing mount/exe data */
Shane Snyder's avatar
Shane Snyder committed
407
        all_ret = darshan_deflate_buffer(pointers, lengths, 2,
408 409
            final_core->comp_buf, &comp_buf_sz);
        if(all_ret)
410
        {
411
            fprintf(stderr, "darshan library warning: unable to compress job data\n");
412
            unlink(logfile_name);
413
        }
414 415 416
        else
        {
            /* write the job information, preallocing space for the log header */
Shane Snyder's avatar
Shane Snyder committed
417
            gz_fp += sizeof(struct darshan_header);
418 419
            all_ret = DARSHAN_MPI_CALL(PMPI_File_write_at)(log_fh, gz_fp,
                final_core->comp_buf, comp_buf_sz, MPI_BYTE, &status);
420 421 422 423 424
            if(all_ret != MPI_SUCCESS)
            {
                fprintf(stderr, "darshan library warning: unable to write job data to log file %s\n",
                        logfile_name);
                unlink(logfile_name);
Shane Snyder's avatar
Shane Snyder committed
425
                
426
            }
427
            gz_fp += comp_buf_sz;
428
        }
429 430
    }

431 432 433 434 435
    /* error out if unable to write job information */
    DARSHAN_MPI_CALL(PMPI_Bcast)(&all_ret, 1, MPI_INT, 0, MPI_COMM_WORLD);
    if(all_ret != 0)
    {
        free(logfile_name);
436
        darshan_core_cleanup(final_core);
437 438
        return;
    }
439 440
    if(internal_timing_flag)
        job2 = DARSHAN_MPI_CALL(PMPI_Wtime)();
441

442 443
    if(internal_timing_flag)
        rec1 = DARSHAN_MPI_CALL(PMPI_Wtime)();
444
    /* write the record name->id hash to the log file */
Shane Snyder's avatar
Shane Snyder committed
445
    final_core->log_header.rec_map.off = gz_fp;
446
    ret = darshan_log_write_record_hash(log_fh, final_core, &gz_fp);
Shane Snyder's avatar
Shane Snyder committed
447
    final_core->log_header.rec_map.len = gz_fp - final_core->log_header.rec_map.off;
448

449
    /* error out if unable to write record hash */
450 451 452 453 454 455
    DARSHAN_MPI_CALL(PMPI_Allreduce)(&ret, &all_ret, 1, MPI_INT,
        MPI_LOR, MPI_COMM_WORLD);
    if(all_ret != 0)
    {
        if(my_rank == 0)
        {
456
            fprintf(stderr, "darshan library warning: unable to write record hash to log file %s\n",
457
                logfile_name);
458
            unlink(logfile_name);
459 460
        }
        free(logfile_name);
461
        darshan_core_cleanup(final_core);
462 463
        return;
    }
Shane Snyder's avatar
Shane Snyder committed
464 465
    if(internal_timing_flag)
        rec2 = DARSHAN_MPI_CALL(PMPI_Wtime)();
466

467 468 469
    mod_shared_recs = malloc(shared_rec_cnt * sizeof(darshan_record_id));
    assert(mod_shared_recs);

470
    /* loop over globally used darshan modules and:
471
     *      - perform shared file reductions, if possible
472
     *      - get final output buffer
473
     *      - compress (zlib) provided output buffer
Shane Snyder's avatar
Shane Snyder committed
474
     *      - append compressed buffer to log file
475 476
     *      - add module index info (file offset/length) to log header
     *      - shutdown the module
477
     */
478
    for(i = 0; i < DARSHAN_MAX_MODS; i++)
479
    {
480
        struct darshan_core_module* this_mod = final_core->mod_array[i];
481
        struct darshan_core_record_ref *ref = NULL;
482
        int mod_shared_rec_cnt = 0;
483
        void* mod_buf = NULL;
484
        int mod_buf_sz = 0;
485
        int j;
486

487
        if(global_mod_use_count[i] == 0)
488 489
        {
            if(my_rank == 0)
490 491 492 493
            {
                final_core->log_header.mod_map[i].off = 0;
                final_core->log_header.mod_map[i].len = 0;
            }
494
            continue;
495
        }
496 497
 
        if(internal_timing_flag)
498
            mod1[i] = DARSHAN_MPI_CALL(PMPI_Wtime)();
499

500
        /* set the shared file list for this module */
501 502
        memset(mod_shared_recs, 0, shared_rec_cnt * sizeof(darshan_record_id));
        for(j = 0; j < shared_rec_cnt; j++)
503 504 505 506
        {
            HASH_FIND(hlink, final_core->rec_hash, &shared_recs[j],
                sizeof(darshan_record_id), ref);
            assert(ref);
507
            if(DARSHAN_MOD_FLAG_ISSET(ref->global_mod_flags, i))
508
            {
509
                mod_shared_recs[mod_shared_rec_cnt++] = shared_recs[j];
510
            }
511
        }
512

513 514 515 516 517
        /* if module is registered locally, get the corresponding output buffer
         * 
         * NOTE: this function can be used to run collective operations across
         * modules, if there are file records shared globally.
         */
518
        if(this_mod)
519
        {
520 521
            this_mod->mod_funcs.get_output_data(MPI_COMM_WORLD, mod_shared_recs,
                mod_shared_rec_cnt, &mod_buf, &mod_buf_sz);
522 523
        }

524
        /* append this module's data to the darshan log */
Shane Snyder's avatar
Shane Snyder committed
525 526 527 528
        final_core->log_header.mod_map[i].off = gz_fp;
        ret = darshan_log_append_all(log_fh, final_core, mod_buf, mod_buf_sz, &gz_fp);
        final_core->log_header.mod_map[i].len =
            gz_fp - final_core->log_header.mod_map[i].off;
529

530
        /* error out if the log append failed */
531 532 533
        DARSHAN_MPI_CALL(PMPI_Allreduce)(&ret, &all_ret, 1, MPI_INT,
            MPI_LOR, MPI_COMM_WORLD);
        if(all_ret != 0)
534
        {
535 536 537 538 539 540 541 542
            if(my_rank == 0)
            {
                fprintf(stderr,
                    "darshan library warning: unable to write %s module data to log file %s\n",
                    darshan_module_names[i], logfile_name);
                unlink(logfile_name);
            }
            free(logfile_name);
543
            darshan_core_cleanup(final_core);
544
            return;
545 546 547
        }

        /* shutdown module if registered locally */
548
        if(this_mod)
549 550 551
        {
            this_mod->mod_funcs.shutdown();
        }
552 553
        if(internal_timing_flag)
            mod2[i] = DARSHAN_MPI_CALL(PMPI_Wtime)();
554 555
    }

556 557
    if(internal_timing_flag)
        header1 = DARSHAN_MPI_CALL(PMPI_Wtime)();
558 559 560 561 562 563
    /* write out log header, after running 2 reduction on header variables:
     *  1) reduce 'partial_flag' variable to determine which modules ran out
     *     of memory for storing I/O data
     *  2) reduce 'mod_ver' array to determine which log format version each
     *     module used for this output log
     */
564 565
    if(my_rank == 0)
    {
566 567 568 569 570 571 572 573
        DARSHAN_MPI_CALL(PMPI_Reduce)(MPI_IN_PLACE,
            &(final_core->log_header.partial_flag), 1, MPI_UINT32_T,
            MPI_BOR, 0, MPI_COMM_WORLD);
        DARSHAN_MPI_CALL(PMPI_Reduce)(MPI_IN_PLACE,
            final_core->log_header.mod_ver, DARSHAN_MAX_MODS, MPI_UINT32_T,
            MPI_MAX, 0, MPI_COMM_WORLD);

        /* rank 0 is responsible for writing the log header */
574 575 576
        /* initialize the remaining header fields */
        strcpy(final_core->log_header.version_string, DARSHAN_LOG_VERSION);
        final_core->log_header.magic_nr = DARSHAN_MAGIC_NR;
577
        final_core->log_header.comp_type = DARSHAN_ZLIB_COMP;
578

Shane Snyder's avatar
Shane Snyder committed
579 580 581
        all_ret = DARSHAN_MPI_CALL(PMPI_File_write_at)(log_fh, 0, &(final_core->log_header),
            sizeof(struct darshan_header), MPI_BYTE, &status);
        if(all_ret != MPI_SUCCESS)
582
        {
Shane Snyder's avatar
Shane Snyder committed
583 584
            fprintf(stderr, "darshan library warning: unable to write header to log file %s\n",
                    logfile_name);
585
            unlink(logfile_name);
586
        }
587
    }
588 589 590 591 592 593 594 595 596
    else
    {
        DARSHAN_MPI_CALL(PMPI_Reduce)(&(final_core->log_header.partial_flag),
            &(final_core->log_header.partial_flag), 1, MPI_UINT32_T,
            MPI_BOR, 0, MPI_COMM_WORLD);
        DARSHAN_MPI_CALL(PMPI_Reduce)(final_core->log_header.mod_ver,
            final_core->log_header.mod_ver, DARSHAN_MAX_MODS, MPI_UINT32_T,
            MPI_MAX, 0, MPI_COMM_WORLD);
    }
597

598 599 600 601 602
    /* error out if unable to write log header */
    DARSHAN_MPI_CALL(PMPI_Bcast)(&all_ret, 1, MPI_INT, 0, MPI_COMM_WORLD);
    if(all_ret != 0)
    {
        free(logfile_name);
603
        darshan_core_cleanup(final_core);
604 605
        return;
    }
606 607
    if(internal_timing_flag)
        header2 = DARSHAN_MPI_CALL(PMPI_Wtime)();
608

609 610 611
    DARSHAN_MPI_CALL(PMPI_File_close)(&log_fh);

    /* if we got this far, there are no errors, so rename from *.darshan_partial
612
     * to *-<logwritetime>.darshan, which indicates that this log file is
613 614
     * complete and ready for analysis
     */
615 616
    if(my_rank == 0)
    {
Shane Snyder's avatar
Shane Snyder committed
617
        if(getenv("DARSHAN_LOGFILE"))
618
        {
619
#ifdef __DARSHAN_GROUP_READABLE_LOGS
Shane Snyder's avatar
Shane Snyder committed
620
            chmod(logfile_name, (S_IRUSR|S_IRGRP));
621
#else
Shane Snyder's avatar
Shane Snyder committed
622
            chmod(logfile_name, (S_IRUSR));
623
#endif
Shane Snyder's avatar
Shane Snyder committed
624 625 626 627 628 629 630 631 632 633 634 635 636 637
        }
        else
        {
            char* tmp_index;
            double end_log_time;
            char* new_logfile_name;

            new_logfile_name = malloc(PATH_MAX);
            if(new_logfile_name)
            {
                new_logfile_name[0] = '\0';
                end_log_time = DARSHAN_MPI_CALL(PMPI_Wtime)();
                strcat(new_logfile_name, logfile_name);
                tmp_index = strstr(new_logfile_name, ".darshan_partial");
638
                sprintf(tmp_index, "_%d.darshan", (int)(end_log_time-start_log_time+1));
Shane Snyder's avatar
Shane Snyder committed
639 640
                rename(logfile_name, new_logfile_name);
                /* set permissions on log file */
641
#ifdef __DARSHAN_GROUP_READABLE_LOGS
Shane Snyder's avatar
Shane Snyder committed
642 643 644 645 646 647
                chmod(new_logfile_name, (S_IRUSR|S_IRGRP));
#else
                chmod(new_logfile_name, (S_IRUSR));
#endif
                free(new_logfile_name);
            }
648
        }
649
    }
650

651
    free(logfile_name);
652
    darshan_core_cleanup(final_core);
653

654
    if(internal_timing_flag)
655
    {
656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689
        double open_tm, open_slowest;
        double header_tm, header_slowest;
        double job_tm, job_slowest;
        double rec_tm, rec_slowest;
        double mod_tm[DARSHAN_MAX_MODS], mod_slowest[DARSHAN_MAX_MODS];
        double all_tm, all_slowest;

        tm_end = DARSHAN_MPI_CALL(PMPI_Wtime)();

        open_tm = open2 - open1;
        header_tm = header2 - header1;
        job_tm = job2 - job1;
        rec_tm = rec2 - rec1;
        all_tm = tm_end - start_log_time;
        for(i = 0;i < DARSHAN_MAX_MODS; i++)
        {
            mod_tm[i] = mod2[i] - mod1[i];
        }

        DARSHAN_MPI_CALL(PMPI_Reduce)(&open_tm, &open_slowest, 1,
            MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
        DARSHAN_MPI_CALL(PMPI_Reduce)(&header_tm, &header_slowest, 1,
            MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
        DARSHAN_MPI_CALL(PMPI_Reduce)(&job_tm, &job_slowest, 1,
            MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
        DARSHAN_MPI_CALL(PMPI_Reduce)(&rec_tm, &rec_slowest, 1,
            MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
        DARSHAN_MPI_CALL(PMPI_Reduce)(&all_tm, &all_slowest, 1,
            MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);
        DARSHAN_MPI_CALL(PMPI_Reduce)(mod_tm, mod_slowest, DARSHAN_MAX_MODS,
            MPI_DOUBLE, MPI_MAX, 0, MPI_COMM_WORLD);

        if(my_rank == 0)
        {
690 691 692 693 694
            fprintf(stderr, "#darshan:<op>\t<nprocs>\t<time>\n");
            fprintf(stderr, "darshan:log_open\t%d\t%f\n", nprocs, open_slowest);
            fprintf(stderr, "darshan:job_write\t%d\t%f\n", nprocs, job_slowest);
            fprintf(stderr, "darshan:hash_write\t%d\t%f\n", nprocs, rec_slowest);
            fprintf(stderr, "darshan:header_write\t%d\t%f\n", nprocs, header_slowest);
695 696 697
            for(i = 0; i < DARSHAN_MAX_MODS; i++)
            {
                if(global_mod_use_count[i])
698
                    fprintf(stderr, "darshan:%s_shutdown\t%d\t%f\n", darshan_module_names[i],
Shane Snyder's avatar
Shane Snyder committed
699
                        nprocs, mod_slowest[i]);
700
            }
701
            fprintf(stderr, "darshan:core_shutdown\t%d\t%f\n", nprocs, all_slowest);
702
        }
703 704 705 706
    }
    
    return;
}
707

Shane Snyder's avatar
Shane Snyder committed
708
/* *********************************** */
709

710
/* construct the darshan log file name */
711
static void darshan_get_logfile_name(char* logfile_name, int jobid, struct tm* start_tm)
712
{
Shane Snyder's avatar
Shane Snyder committed
713
    char* user_logfile_name;
714 715 716
    char* logpath;
    char* logname_string;
    char* logpath_override = NULL;
717
#ifdef __DARSHAN_LOG_ENV
718 719 720 721 722 723 724 725 726
    char env_check[256];
    char* env_tok;
#endif
    uint64_t hlevel;
    char hname[HOST_NAME_MAX];
    uint64_t logmod;
    char cuser[L_cuserid] = {0};
    int ret;

Shane Snyder's avatar
Shane Snyder committed
727 728 729 730 731 732 733 734 735 736 737 738 739 740 741
    /* first, check if user specifies a complete logpath to use */
    user_logfile_name = getenv("DARSHAN_LOGFILE");
    if(user_logfile_name)
    {
        if(strlen(user_logfile_name) >= (PATH_MAX-1))
        {
            fprintf(stderr, "darshan library warning: user log file name too long.\n");
            logfile_name[0] = '\0';
        }
        else
        {
            strcpy(logfile_name, user_logfile_name);
        }
    }
    else
742
    {
Shane Snyder's avatar
Shane Snyder committed
743 744
        /* otherwise, generate the log path automatically */

745 746
        /* Use DARSHAN_LOG_PATH_OVERRIDE for the value or __DARSHAN_LOG_PATH */
        logpath = getenv(DARSHAN_LOG_PATH_OVERRIDE);
Shane Snyder's avatar
Shane Snyder committed
747 748
        if(!logpath)
        {
749 750
#ifdef __DARSHAN_LOG_PATH
            logpath = __DARSHAN_LOG_PATH;
751
#endif
Shane Snyder's avatar
Shane Snyder committed
752
        }
753

Shane Snyder's avatar
Shane Snyder committed
754 755 756 757 758 759 760 761 762 763
        /* get the username for this job.  In order we will try each of the
         * following until one of them succeeds:
         *
         * - cuserid()
         * - getenv("LOGNAME")
         * - snprintf(..., geteuid());
         *
         * Note that we do not use getpwuid() because it generally will not
         * work in statically compiled binaries.
         */
764 765

#ifndef DARSHAN_DISABLE_CUSERID
Shane Snyder's avatar
Shane Snyder committed
766
        cuserid(cuser);
767 768
#endif

Shane Snyder's avatar
Shane Snyder committed
769 770
        /* if cuserid() didn't work, then check the environment */
        if(strcmp(cuser, "") == 0)
771
        {
Shane Snyder's avatar
Shane Snyder committed
772 773 774 775 776
            logname_string = getenv("LOGNAME");
            if(logname_string)
            {
                strncpy(cuser, logname_string, (L_cuserid-1));
            }
777 778
        }

Shane Snyder's avatar
Shane Snyder committed
779 780 781 782 783 784
        /* if cuserid() and environment both fail, then fall back to uid */
        if(strcmp(cuser, "") == 0)
        {
            uid_t uid = geteuid();
            snprintf(cuser, sizeof(cuser), "%u", uid);
        }
785

Shane Snyder's avatar
Shane Snyder committed
786 787 788 789
        /* generate a random number to help differentiate the log */
        hlevel=DARSHAN_MPI_CALL(PMPI_Wtime)() * 1000000;
        (void)gethostname(hname, sizeof(hname));
        logmod = darshan_hash((void*)hname,strlen(hname),hlevel);
790

Shane Snyder's avatar
Shane Snyder committed
791 792 793 794
        /* see if darshan was configured using the --with-logpath-by-env
         * argument, which allows the user to specify an absolute path to
         * place logs via an env variable.
         */
795
#ifdef __DARSHAN_LOG_ENV
Shane Snyder's avatar
Shane Snyder committed
796
        /* just silently skip if the environment variable list is too big */
797
        if(strlen(__DARSHAN_LOG_ENV) < 256)
798
        {
Shane Snyder's avatar
Shane Snyder committed
799
            /* copy env variable list to a temporary buffer */
800
            strcpy(env_check, __DARSHAN_LOG_ENV);
Shane Snyder's avatar
Shane Snyder committed
801 802 803
            /* tokenize the comma-separated list */
            env_tok = strtok(env_check, ",");
            if(env_tok)
804
            {
Shane Snyder's avatar
Shane Snyder committed
805
                do
806
                {
Shane Snyder's avatar
Shane Snyder committed
807 808 809 810 811 812 813 814 815
                    /* check each env variable in order */
                    logpath_override = getenv(env_tok);
                    if(logpath_override)
                    {
                        /* stop as soon as we find a match */
                        break;
                    }
                }while((env_tok = strtok(NULL, ",")));
            }
816 817 818
        }
#endif

Shane Snyder's avatar
Shane Snyder committed
819
        if(logpath_override)
820
        {
Shane Snyder's avatar
Shane Snyder committed
821 822 823 824 825 826 827 828 829 830 831 832 833 834 835
            ret = snprintf(logfile_name, PATH_MAX,
                "%s/%s_%s_id%d_%d-%d-%d-%" PRIu64 ".darshan_partial",
                logpath_override,
                cuser, __progname, jobid,
                (start_tm->tm_mon+1),
                start_tm->tm_mday,
                (start_tm->tm_hour*60*60 + start_tm->tm_min*60 + start_tm->tm_sec),
                logmod);
            if(ret == (PATH_MAX-1))
            {
                /* file name was too big; squish it down */
                snprintf(logfile_name, PATH_MAX,
                    "%s/id%d.darshan_partial",
                    logpath_override, jobid);
            }
836
        }
Shane Snyder's avatar
Shane Snyder committed
837
        else if(logpath)
838
        {
Shane Snyder's avatar
Shane Snyder committed
839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858
            ret = snprintf(logfile_name, PATH_MAX,
                "%s/%d/%d/%d/%s_%s_id%d_%d-%d-%d-%" PRIu64 ".darshan_partial",
                logpath, (start_tm->tm_year+1900),
                (start_tm->tm_mon+1), start_tm->tm_mday,
                cuser, __progname, jobid,
                (start_tm->tm_mon+1),
                start_tm->tm_mday,
                (start_tm->tm_hour*60*60 + start_tm->tm_min*60 + start_tm->tm_sec),
                logmod);
            if(ret == (PATH_MAX-1))
            {
                /* file name was too big; squish it down */
                snprintf(logfile_name, PATH_MAX,
                    "%s/id%d.darshan_partial",
                    logpath, jobid);
            }
        }
        else
        {
            logfile_name[0] = '\0';
859 860 861 862
        }
    }

    return;
863 864
}

865
/* record any hints used to write the darshan log in the log header */
866
static void darshan_log_record_hints_and_ver(struct darshan_core_runtime* core)
867 868 869 870 871 872 873 874 875
{
    char* hints;
    char* header_hints;
    int meta_remain = 0;
    char* m;

    /* check environment variable to see if the default MPI file hints have
     * been overridden
     */
876
    hints = getenv(DARSHAN_LOG_HINTS_OVERRIDE);
877 878
    if(!hints)
    {
879
        hints = __DARSHAN_LOG_HINTS;
880 881 882 883 884 885 886 887 888 889
    }

    if(!hints || strlen(hints) < 1)
        return;

    header_hints = strdup(hints);
    if(!header_hints)
        return;