codes-darshan-io-wrkld.c 28.3 KB
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/*
 * Copyright (C) 2013 University of Chicago.
 * See COPYRIGHT notice in top-level directory.
 *
 */
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#include <assert.h>
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#include "codes/codes-workload.h"
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#include "codes/quickhash.h"
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#include "codes-workload-method.h"
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#include "darshan-logutils.h"
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#define DEF_INTER_IO_DELAY_PCT 0.2
#define DEF_INTER_CYC_DELAY_PCT 0.4

#define IO_IS_IN_SIZE_BIN_RANGE(size, bin_ndx, bin_min_sizes)                       \
        ((bin_ndx == 9) ?                                                           \
        (size >= bin_min_sizes[bin_ndx]) :                                          \
        ((size >= bin_min_sizes[bin_ndx]) && (size < bin_min_sizes[bin_ndx + 1])))

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/* CODES workload API functions for workloads generated from darshan logs*/
static int darshan_io_workload_load(const char *params, int rank);
static void darshan_io_workload_get_next(int rank, struct codes_workload_op *op);

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/* helper functions for implementing the darshan workload generator */
static void generate_psx_ind_file_events(struct darshan_file *file);
static double generate_psx_open_event(struct darshan_file *file, int create_flag,
                                      double meta_op_time, double cur_time);
static double generate_psx_close_event(struct darshan_file *file, double meta_op_time,
                                       double cur_time);
static double generate_barrier_event(struct darshan_file *file, int64_t root, double cur_time);
static double generate_psx_ind_io_events(struct darshan_file *file, int64_t io_ops_this_cycle,
                                         int64_t open_ndx, double inter_io_delay, 
                                         double meta_op_time, double cur_time);
static void determine_io_params(struct darshan_file *file, int write_flag, int coll_flag,
                                int64_t io_cycles, size_t *io_sz, off_t *io_off);
static void calc_io_delays(struct darshan_file *file, int64_t num_opens, int64_t num_io_ops,
                           double delay_per_cycle, double *first_io_delay, double *close_delay,
                           double *inter_open_delay, double *inter_io_delay);
static void file_sanity_check(struct darshan_file *file, struct darshan_job *job);

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/* workload method name and function pointers for the CODES workload API */
struct codes_workload_method darshan_io_workload_method =
{
    .method_name = "darshan_io_workload",
    .codes_workload_load = darshan_io_workload_load,
    .codes_workload_get_next = darshan_io_workload_get_next,
};

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/* info about this darshan workload group needed by bgp model */
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/* TODO: is this needed for darshan workloads? */
/* TODO: does this need to be stored in the rank context to support multiple workloads? */
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/* hash table to store per-rank workload contexts */
//static struct qhash_table *rank_tbl = NULL;
//static int rank_tbl_pop = 0;

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/* load the workload generator for this rank, given input params */
static int darshan_io_workload_load(const char *params, int rank)
{
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    darshan_params *d_params = (darshan_params *)params;
    darshan_fd logfile_fd;
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    struct darshan_job job;
    struct darshan_file next_file;
    int ret;
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    if (!d_params)
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        return -1;

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    /* (re)seed the random number generator */
    srand(time(NULL));
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    /* open the darshan log to begin reading in file i/o info */
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    logfile_fd = darshan_log_open(d_params->log_file_path, "r");
    if (logfile_fd < 0)
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        return -1;
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    /* get the per-job stats from the log */
    ret = darshan_log_getjob(logfile_fd, &job);
    if (ret < 0)
    {
        darshan_log_close(logfile_fd);
        return -1;
    }

    /* loop over all files contained in the log file */
    while ((ret = darshan_log_getfile(logfile_fd, &job, &next_file)) > 0)
    {
        /* generate all i/o events contained in this independent file */
        if (next_file.rank == rank)
        {
            /* make sure the file i/o counters are valid */
            file_sanity_check(&next_file, &job);

            /* generate i/o events and store them in this rank's workload context */
            generate_psx_ind_file_events(&next_file);
        }
        /* generate all i/o events involving this rank in this collective file */
        else if (next_file.rank == -1)
        {
            /* make sure the file i/o counters are valid */
            file_sanity_check(&next_file, &job);
        }
    }

    if (ret < 0)
        return -1;

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    darshan_log_close(logfile_fd);
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    return 0;
}

/* pull the next event (independent or collective) for this rank from its event context */
static void darshan_io_workload_get_next(int rank, struct codes_workload_op *op)
{

    return;
}

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/* return the workload info needed by the bgp model */
/* TODO: do we really need this? */
static void *darshan_io_workload_get_info(int rank)
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{
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    return &(darshan_workload_info);
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}
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/* * * * */
  /* * * * */
/* * * * */

/* generate events for an independently opened file, and store these events */
static void generate_psx_ind_file_events(
    struct darshan_file *file)
{
#if 0
    int64_t io_ops_this_cycle;
    double cur_time = file->fcounters[CP_F_OPEN_TIMESTAMP];
    double delay_per_open;
    double first_io_delay = 0.0;
    double close_delay = 0.0;
    double inter_open_delay = 0.0;
    double inter_io_delay = 0.0;
    double meta_op_time;
    int create_flag;
    int64_t i;

    /* if the file was never really opened, just return because we have no timing info */
    if (file->counters[CP_POSIX_OPENS] == 0)
        return;

    /* determine delay available per open-io-close cycle */
    delay_per_open = (file->fcounters[CP_F_CLOSE_TIMESTAMP] - file->fcounters[CP_F_OPEN_TIMESTAMP] -
                     file->fcounters[CP_F_POSIX_READ_TIME] - file->fcounters[CP_F_POSIX_WRITE_TIME] -
                     file->fcounters[CP_F_POSIX_META_TIME]) / file->counters[CP_POSIX_OPENS];

    /* calculate synthetic delay values */
    calc_io_delays(file, file->counters[CP_POSIX_OPENS],
                   file->counters[CP_POSIX_READS] + file->counters[CP_POSIX_WRITES],
                   delay_per_open, &first_io_delay, &close_delay,
                   &inter_open_delay, &inter_io_delay);

    /* calculate average meta op time (for i/o and opens/closes) */
    /* TODO: this needs to be updated when we add in stat, seek, etc. */
    meta_op_time = file->fcounters[CP_F_POSIX_META_TIME] / ((2 * file->counters[CP_POSIX_OPENS]) +
                   file->counters[CP_POSIX_READS] + file->counters[CP_POSIX_WRITES]);

    /* TODO: FIX ME */
    create_flag = 0;

    /* generate open/io/close events for all cycles */
    /* TODO: add stats */
    for (i = 0; file->counters[CP_POSIX_OPENS]; i++, file->counters[CP_POSIX_OPENS]--)
    {
        /* generate an open event */
        cur_time = generate_psx_open_event(file, create_flag, meta_op_time, cur_time);
        create_flag = 0;

        /* account for potential delay from first open to first io */
        cur_time += first_io_delay;

        io_ops_this_cycle = ceil((double)(file->counters[CP_POSIX_READS] +
                                 file->counters[CP_POSIX_WRITES]) /
                                 file->counters[CP_POSIX_OPENS]);

        /* perform the calculated number of i/o operations for this file open */
        cur_time = generate_psx_ind_io_events(file, io_ops_this_cycle, i, inter_io_delay,
                                              meta_op_time, cur_time);

        /* account for potential delay from last io to close */
        cur_time += close_delay;

        /* generate a close for the open event at the start of the loop */
        cur_time = generate_psx_close_event(file, meta_op_time, cur_time);

        /* account for potential interopen delay if more than one open */
        if (file->counters[CP_POSIX_OPENS] > 1)
        {
            cur_time += inter_open_delay;
        }
    }
#endif

    return;
}

/* fill in an open event structure and store it with the rank context */
static double generate_psx_open_event(
    struct darshan_file *file, int create_flag, double meta_op_time, double cur_time)
{
#if 0
    struct darshan_event next_event = { .rank = file->rank,
                                        .type = POSIX_OPEN,
                                        .start_time = cur_time
                                      };

    /* identify the file hash value and whether the file was created or not */
    next_event.event_params.open.file = file->hash;
    next_event.event_params.open.create_flag = create_flag;

    /* set the end time of the event based on time spent in POSIX meta operations */
    cur_time += meta_op_time;
    next_event.end_time = cur_time;

    /* TODO: store the open event */
#endif

    return cur_time;
}

/* fill in a close event structure and store it with the rank context */
static double generate_psx_close_event(
    struct darshan_file *file, double meta_op_time, double cur_time)
{
#if 0
    struct darshan_event next_event = { .rank = file->rank,
                                        .type = POSIX_CLOSE,
                                        .start_time = cur_time
                                      };

    next_event.event_params.close.file = file->hash;

    /* set the end time of the event based on time spent in POSIX meta operations */
    cur_time += meta_op_time;
    next_event.end_time = cur_time;

    /* TODO: store the close event */
#endif

    return cur_time;
}

/* fill in a barrier event structure and store it with the rank context */
static double generate_barrier_event(
    struct darshan_file *file, int64_t root, double cur_time)
{
#if 0
    struct darshan_event next_event = { .rank = file->rank,
                                        .type = BARRIER,
                                        .start_time = cur_time,
                                        .end_time = cur_time
                                      };

    next_event.event_params.barrier.proc_count = -1; /* -1 for all procs (nprocs) */
    next_event.event_params.barrier.root = root;

    cur_time += .000001; /* small synthetic delay representing time to barrier */
    next_event.end_time = cur_time;

    /* TODO: store the barrier event */
#endif

    return cur_time;
}

/* generate all i/o events for one independent file open and store them with the rank context */
static double generate_psx_ind_io_events(
    struct darshan_file *file, int64_t io_ops_this_cycle, int64_t open_ndx,
    double inter_io_delay, double meta_op_time, double cur_time)
{
#if 0
    static int rw = -1; /* rw = 1 for write, 0 for read, -1 for uninitialized */
    static int64_t io_ops_this_rw;
    static double rd_bw = 0.0, wr_bw = 0.0;
    int64_t psx_rw_ops_remaining = file->counters[CP_POSIX_READS] + file->counters[CP_POSIX_WRITES];
    double io_op_time;
    size_t io_sz;
    off_t io_off;
    int64_t i;
    struct darshan_event next_event = { .rank = file->rank };

    /* if there are no i/o ops, just return immediately */
    if (!io_ops_this_cycle)
        return cur_time;

    /* initialze static variables when a new file is opened */
    if (rw == -1)
    {
        /* initialize rw to be the first i/o operation found in the log */
        if (file->fcounters[CP_F_WRITE_START_TIMESTAMP] == 0.0)
            rw = 0;
        else if (file->fcounters[CP_F_READ_START_TIMESTAMP] == 0.0)
            rw = 1;
        else
            rw = (file->fcounters[CP_F_READ_START_TIMESTAMP] <
                  file->fcounters[CP_F_WRITE_START_TIMESTAMP]) ? 0 : 1;

        /* determine how many io ops to do before next rw switch */
        if (!rw)
            io_ops_this_rw = file->counters[CP_POSIX_READS] /
                             ((file->counters[CP_RW_SWITCHES] / 2) + 1);
        else
            io_ops_this_rw = file->counters[CP_POSIX_WRITES] /
                             ((file->counters[CP_RW_SWITCHES] / 2) + 1);

        /* initialize the rd and wr bandwidth values using total io size and time */
        if (file->fcounters[CP_F_POSIX_READ_TIME])
            rd_bw = file->counters[CP_BYTES_READ] / file->fcounters[CP_F_POSIX_READ_TIME];
        if (file->fcounters[CP_F_POSIX_WRITE_TIME])
            wr_bw = file->counters[CP_BYTES_WRITTEN] / file->fcounters[CP_F_POSIX_WRITE_TIME];
    }

    /* loop to generate all reads/writes for this open/close sequence */
    for (i = 0; i < io_ops_this_cycle; i++)
    {
        /* calculate what value to use for i/o size and offset */
        determine_io_params(file, rw, 0, file->counters[CP_POSIX_OPENS], &io_sz, &io_off);
        if (!rw)
        {
            /* generate a read event */
            next_event.type = POSIX_READ;
            next_event.start_time = cur_time;
            next_event.event_params.read.file = file->hash;
            next_event.event_params.read.size = io_sz;
            next_event.event_params.read.offset = io_off;

            /* set the end time based on observed bandwidth and io size */
            if (rd_bw == 0.0)
                io_op_time = 0.0;
            else
                io_op_time = (next_event.event_params.read.size / rd_bw);

            /* update time, accounting for metadata time */
            cur_time += (io_op_time + meta_op_time);
            next_event.end_time = cur_time;
            file->counters[CP_POSIX_READS]--;
        }
        else
        {
            /* generate a write event */
            next_event.type = POSIX_WRITE;
            next_event.start_time = cur_time;
            next_event.event_params.write.file = file->hash;
            next_event.event_params.write.size = io_sz;

            next_event.event_params.write.offset = io_off;

            /* set the end time based on observed bandwidth and io size */
            if (wr_bw == 0.0)
                io_op_time = 0.0;
            else
                io_op_time = (next_event.event_params.write.size / wr_bw);

            /* update time, accounting for metadata time */
            cur_time += (io_op_time + meta_op_time);
            next_event.end_time = cur_time;
            file->counters[CP_POSIX_WRITES]--;
        }
        psx_rw_ops_remaining--;
        io_ops_this_rw--;
        assert(file->counters[CP_POSIX_READS] >= 0);
        assert(file->counters[CP_POSIX_WRITES] >= 0);

        /* TODO: store the i/o event */

        /* determine whether to toggle between reads and writes */
        if (!io_ops_this_rw && psx_rw_ops_remaining)
        {
            /* toggle the read/write flag */
            rw ^= 1;
            file->counters[CP_RW_SWITCHES]--;

            /* determine how many io ops to do before next rw switch */
            if (!rw)
                io_ops_this_rw = file->counters[CP_POSIX_READS] /
                                 ((file->counters[CP_RW_SWITCHES] / 2) + 1);
            else
                io_ops_this_rw = file->counters[CP_POSIX_WRITES] /
                                 ((file->counters[CP_RW_SWITCHES] / 2) + 1);
        }

        if (i != (io_ops_this_cycle - 1))
        {
            /* update current time to account for possible delay between i/o operations */
            cur_time += (inter_io_delay / (io_ops_this_cycle - 1));
        }
    }

    /* reset the static rw flag if this is the last open-close cycle for this file */
    if (file->counters[CP_POSIX_OPENS] == 1)
    {
        rw = -1;
    }
#endif

    return cur_time;
}

static void determine_io_params(
    struct darshan_file *file, int write_flag, int coll_flag, int64_t io_cycles, 
    size_t *io_sz, off_t *io_off)
{
    static int seq_rd_flag = -1;
    static int seq_wr_flag = -1;
    static uint64_t next_rd_off = 0;
    static uint64_t next_wr_off = 0;
    static int64_t rd_common_accesses[4] = { 0, 0, 0, 0 };
    static int64_t wr_common_accesses[4] = { 0, 0, 0, 0 };
    static int all_common_flag = -1;
    int64_t *size_bins; /* 10 size bins for io operations */
    int64_t *common_accesses = &(file->counters[CP_ACCESS1_ACCESS]); /* 4 common accesses */
    int64_t *common_access_counts = &(file->counters[CP_ACCESS1_COUNT]); /* common access counts */
    int64_t *total_io_size;
    int64_t last_io_byte;
    int64_t tmp_byte_counter = 0;
    double weighted_rand_counter = 0.0;
    int size_bin_ndx;
    int i, j = 0;
    int64_t bin_min_size[10] = { 0, 100, 1024, 10 * 1024, 100 * 1024, 1024 * 1024, 4 * 1024 * 1024,
                                 10 * 1024 * 1024, 100 * 1024 * 1024, 1024 * 1024 * 1024 };
    int64_t bin_def_size[10] = { 40, 512, 4 * 1024, 60 * 1024, 512 * 1024, 2 * 1024 * 1024,
                                 6 * 1024 * 1024, 40 * 1024 * 1024, 400 * 1024 * 1024,
                                 1 * 1024 * 1024 * 1024 };

    /* determine how to assign common access counters to reads and/or writes */
    if (all_common_flag == -1)
    {
        for (i = 0; i < 4; i++)
        {
            tmp_byte_counter += (common_accesses[i] * common_access_counts[i]);
        }

        if (tmp_byte_counter == (file->counters[CP_BYTES_WRITTEN] + file->counters[CP_BYTES_READ]))
        {
            all_common_flag = 1;
        }
        else
        {
            all_common_flag = 0;
        }
    }

    /* assign data values depending on whether the operation is a read or write */
    if (write_flag)
    {
        size_bins = &(file->counters[CP_SIZE_WRITE_0_100]);
        total_io_size = &(file->counters[CP_BYTES_WRITTEN]);
        last_io_byte = file->counters[CP_MAX_BYTE_WRITTEN];

        if (seq_wr_flag == -1)
        {
            if ((file->counters[CP_POSIX_WRITES] -
                ((*total_io_size - last_io_byte - 1) / (last_io_byte + 1)) - 1) ==
                file->counters[CP_SEQ_WRITES])
            {
                seq_wr_flag = 1;
            }
            else
            {
                seq_wr_flag = 0;
            }
        }
    }
    else
    {
        size_bins = &(file->counters[CP_SIZE_READ_0_100]);
        total_io_size = &(file->counters[CP_BYTES_READ]);
        last_io_byte = file->counters[CP_MAX_BYTE_READ];

        if (seq_rd_flag == -1)
        {
            if ((file->counters[CP_POSIX_READS] -
                ((*total_io_size - last_io_byte - 1) / (last_io_byte + 1)) - 1) ==
                file->counters[CP_SEQ_READS])
            {
                seq_rd_flag = 1;
            }
            else
            {
                seq_rd_flag = 0;
            }
        }
    }

    *io_sz = 0;
    if ((*total_io_size ==  0) || (write_flag && (file->counters[CP_POSIX_WRITES] == 1)) ||
        (!write_flag && (file->counters[CP_POSIX_READS] == 1)))
    {
        if (*total_io_size >= 0)
            *io_sz = *total_io_size;
    }
    else if (all_common_flag)
    {
        for (i = 0; i < 4; i++)
        {
            if (!write_flag && rd_common_accesses[i])
            {
                *io_sz = common_accesses[i];
                rd_common_accesses[i]--;
                common_access_counts[i]--;
                break;
            }
            else if (write_flag && wr_common_accesses[i])
            {
                *io_sz = common_accesses[i];
                wr_common_accesses[i]--;
                common_access_counts[i]--;
                break;
            }
        }

        if (*io_sz == 0)
        {
            for (i = 0; i < 4; i++)
            {
                if (write_flag)
                {
                    wr_common_accesses[i] = (common_access_counts[i] / io_cycles);
                    if ((*io_sz == 0) && wr_common_accesses[i])
                    {
                        *io_sz = common_accesses[i];
                        wr_common_accesses[i]--;
                        common_access_counts[i]--;
                    }
                }
                else
                {
                    rd_common_accesses[i] = (common_access_counts[i] / io_cycles);
                    if ((*io_sz == 0) && rd_common_accesses[i])
                    {
                        *io_sz = common_accesses[i];
                        rd_common_accesses[i]--;
                        common_access_counts[i]--;
                    }
                }
            }
        }
        assert(*io_sz);
    }
    else
    {
        /* try to assign a common access first */
        for (i = 0; i < 10; i++)
        {
            for (j = 0; j < 4; j++)
            {
                if (size_bins[i] && common_access_counts[j] &&
                    IO_IS_IN_SIZE_BIN_RANGE(common_accesses[j], i, bin_min_size))
                {
                    *io_sz = common_accesses[j];
                    common_access_counts[j]--;
                    break;
                }
            }
            if (*io_sz)
                break;
        }

        /* if no common accesses left, then assign a random io size */
        if (*io_sz == 0)
        {
            size_bin_ndx = rand() % 10;
            for (i = 0; i <  10; i++)
            {
                if (size_bins[size_bin_ndx])
                {
                    *io_sz = bin_def_size[size_bin_ndx];
                    break;
                }
                size_bin_ndx = (size_bin_ndx + 1) % 10;
            }
        }
        assert(*io_sz);
    }

    *total_io_size -= *io_sz;
    for (i = 0; i < 10; i++)
    {
        if (IO_IS_IN_SIZE_BIN_RANGE(*io_sz, i, bin_min_size))
            size_bins[i]--;
    }

    /* next, determine the offset to use */

    /*  for now we just assign a random offset that makes sure not to write past the recorded
     *  last byte written in the file.
     */
    if (*io_sz == 0)
    {
        *io_off = last_io_byte + 1;
    }
    else if (write_flag && seq_wr_flag)
    {
        if ((next_wr_off + *io_sz) > (last_io_byte + 1))
            next_wr_off = 0;

        *io_off = next_wr_off;
        next_wr_off += *io_sz;
    }
    else if (!write_flag && seq_rd_flag)
    {
        if ((next_rd_off + *io_sz) > (last_io_byte + 1))
            next_rd_off = 0;

        *io_off = next_rd_off;
        next_rd_off += *io_sz;
    }
    else if (*io_sz < last_io_byte)
    {
        *io_off = (off_t)rand() % (last_io_byte - *io_sz);
    }
    else
    {
        *io_off = 0;
    }

    /* reset static variable if this is the last i/o op for this file */
    if ((file->counters[CP_POSIX_READS] + file->counters[CP_POSIX_WRITES]) == 1)
    {
        next_rd_off = next_wr_off = 0;
        seq_wr_flag = seq_rd_flag = -1;
        all_common_flag = -1;
        for (i = 0; i < 4; i++)
            rd_common_accesses[i] = wr_common_accesses[i] = 0;
    }

    return;
}

/* calculate the simulated "delay" between different i/o events using delay info
 * from the file counters */
static void calc_io_delays(
    struct darshan_file *file, int64_t num_opens, int64_t num_io_ops, double delay_per_cycle,
    double *first_io_delay, double *close_delay, double *inter_open_delay, double *inter_io_delay)
{
    double first_io_time, last_io_time;
    double first_io_pct, close_pct, inter_open_pct, inter_io_pct;
    double total_delay_pct;
    double tmp_inter_io_pct, tmp_inter_open_pct;

    if (delay_per_cycle > 0.0)
    {
        /* determine the time of the first io operation */
        if (!file->fcounters[CP_F_WRITE_START_TIMESTAMP])
            first_io_time = file->fcounters[CP_F_READ_START_TIMESTAMP];
        else if (!file->fcounters[CP_F_READ_START_TIMESTAMP])
            first_io_time = file->fcounters[CP_F_WRITE_START_TIMESTAMP];
        else if (file->fcounters[CP_F_READ_START_TIMESTAMP] <
                 file->fcounters[CP_F_WRITE_START_TIMESTAMP])
            first_io_time = file->fcounters[CP_F_READ_START_TIMESTAMP];
        else
            first_io_time = file->fcounters[CP_F_WRITE_START_TIMESTAMP];

        /* determine the time of the last io operation */
        if (file->fcounters[CP_F_READ_END_TIMESTAMP] > file->fcounters[CP_F_WRITE_END_TIMESTAMP])
            last_io_time = file->fcounters[CP_F_READ_END_TIMESTAMP];
        else
            last_io_time = file->fcounters[CP_F_WRITE_END_TIMESTAMP];

        /* no delay contribution for inter-open delay if there is only a single open */
        if (num_opens > 1)
            inter_open_pct = DEF_INTER_CYC_DELAY_PCT;

        /* no delay contribution for inter-io delay if there is one or less io op */
        if (num_io_ops > 1)
            inter_io_pct = DEF_INTER_IO_DELAY_PCT;

        /* determine delay contribution for first io and close delays */
        if (first_io_time != 0.0)
        {
            first_io_pct = (first_io_time - file->fcounters[CP_F_OPEN_TIMESTAMP]) / delay_per_cycle;
            close_pct = (file->fcounters[CP_F_CLOSE_TIMESTAMP] - last_io_time) / delay_per_cycle;
        }
        else
        {
            first_io_pct = 0.0;
            close_pct = 1 - inter_open_pct;
        }

        /* adjust per open delay percentages using a simple heuristic */
        total_delay_pct = inter_open_pct + inter_io_pct + first_io_pct + close_pct;
        if ((total_delay_pct < 1) && (inter_open_pct || inter_io_pct))
        {
            /* only adjust inter-open and inter-io delays if we underestimate */
            tmp_inter_open_pct = (inter_open_pct / (inter_open_pct + inter_io_pct)) *
                                 (1 - first_io_pct - close_pct);
            tmp_inter_io_pct = (inter_io_pct / (inter_open_pct + inter_io_pct)) *
                               (1 - first_io_pct - close_pct);
            inter_open_pct = tmp_inter_open_pct;
            inter_io_pct = tmp_inter_io_pct;
        }
        else
        {
            inter_open_pct += (inter_open_pct / total_delay_pct) * (1 - total_delay_pct);
            inter_io_pct += (inter_io_pct / total_delay_pct) * (1 - total_delay_pct);
            first_io_pct += (first_io_pct / total_delay_pct) * (1 - total_delay_pct);
            close_pct += (close_pct / total_delay_pct) * (1 - total_delay_pct);
        }

        *first_io_delay = (first_io_pct * delay_per_cycle);
        *close_delay = (close_pct * delay_per_cycle);
        *inter_open_delay = (inter_open_pct * delay_per_cycle);
        *inter_io_delay = (inter_io_pct * delay_per_cycle);
    }

    return;
}

/* check to make sure file stats are valid and properly formatted */
static void file_sanity_check(
    struct darshan_file *file, struct darshan_job *job)
{
    assert(file->counters[CP_POSIX_OPENS] != -1);
    assert(file->fcounters[CP_F_OPEN_TIMESTAMP] != -1);
    assert(file->counters[CP_COLL_OPENS] != -1);
    assert(file->fcounters[CP_F_CLOSE_TIMESTAMP] != -1);
    assert(file->counters[CP_POSIX_READS] != -1);
    assert(file->counters[CP_POSIX_WRITES] != -1);
    assert(file->fcounters[CP_F_POSIX_READ_TIME] != -1);
    assert(file->fcounters[CP_F_POSIX_WRITE_TIME] != -1);
    assert(file->fcounters[CP_F_POSIX_META_TIME] != -1);
    assert(file->fcounters[CP_F_READ_START_TIMESTAMP] != -1);
    assert(file->fcounters[CP_F_WRITE_START_TIMESTAMP] != -1);
    assert(file->fcounters[CP_F_READ_END_TIMESTAMP] != -1);
    assert(file->fcounters[CP_F_WRITE_END_TIMESTAMP] != -1);
    assert(file->counters[CP_BYTES_READ] != -1);
    assert(file->counters[CP_BYTES_WRITTEN] != -1);
    assert(file->counters[CP_RW_SWITCHES] != -1);

    /* adjust timestamps if they are given in absolute unix time */
    if (file->fcounters[CP_F_OPEN_TIMESTAMP] > job->start_time)
    {
        file->fcounters[CP_F_OPEN_TIMESTAMP] -= job->start_time;
        if (file->fcounters[CP_F_OPEN_TIMESTAMP] < 0.0)
            file->fcounters[CP_F_OPEN_TIMESTAMP] = 0.0;

        file->fcounters[CP_F_READ_START_TIMESTAMP] -= job->start_time;
        if (file->fcounters[CP_F_READ_START_TIMESTAMP] < 0.0)
            file->fcounters[CP_F_READ_START_TIMESTAMP] = 0.0;

        file->fcounters[CP_F_WRITE_START_TIMESTAMP] -= job->start_time;
        if (file->fcounters[CP_F_WRITE_START_TIMESTAMP] < 0.0)
            file->fcounters[CP_F_WRITE_START_TIMESTAMP] = 0.0;

        file->fcounters[CP_F_CLOSE_TIMESTAMP] -= job->start_time;
        if (file->fcounters[CP_F_CLOSE_TIMESTAMP] < 0.0)
            file->fcounters[CP_F_CLOSE_TIMESTAMP] = 0.0;

        file->fcounters[CP_F_READ_END_TIMESTAMP] -= job->start_time;
        if (file->fcounters[CP_F_READ_END_TIMESTAMP] < 0.0)
            file->fcounters[CP_F_READ_END_TIMESTAMP] = 0.0;

        file->fcounters[CP_F_WRITE_END_TIMESTAMP] -= job->start_time;
        if (file->fcounters[CP_F_WRITE_END_TIMESTAMP] < 0.0)
            file->fcounters[CP_F_WRITE_END_TIMESTAMP] = 0.0;
    }

    /* set file close time to the end of execution if it is not given */
    if (file->fcounters[CP_F_CLOSE_TIMESTAMP] == 0.0)
        file->fcounters[CP_F_CLOSE_TIMESTAMP] = job->end_time - job->start_time + 1;

    /* collapse fopen/fread/etc. calls into the corresponding open/read/etc. counters */
    file->counters[CP_POSIX_OPENS] += file->counters[CP_POSIX_FOPENS];
    file->counters[CP_POSIX_READS] += file->counters[CP_POSIX_FREADS];
    file->counters[CP_POSIX_WRITES] += file->counters[CP_POSIX_FWRITES];

    return;
}