mxq_job.c

#define _GNU_SOURCE

#include <stdio.h>
#include <mysql.h>
#include <errno.h>
#include <assert.h>
#include <unistd.h>
#include <libgen.h>
#include <string.h>

#include <sys/resource.h>

#include "mx_util.h"
#include "mx_log.h"

#include "mxq_group.h"
#include "mxq_job.h"

#define JOB_FIELDS_CNT 36
#define JOB_FIELDS \
                " job_id, " \
                " job_status, " \
                " job_flags, " \
                " job_priority, " \
                " group_id, " \
                " job_workdir, " \
                " job_argc, " \
                " job_argv, " \
                " job_stdout, " \
                " job_stderr, " \
                " job_umask, " \
                " host_submit, " \
                " host_id, " \
                " server_id, " \
                " host_hostname, " \
                " host_pid, " \
                " host_slots, " \
                " UNIX_TIMESTAMP(date_submit) as date_submit, " \
                " UNIX_TIMESTAMP(date_start) as date_start, " \
                " UNIX_TIMESTAMP(date_end) as date_end, " \
                " stats_max_sumrss, " \
                " stats_status, " \
                " stats_utime_sec, " \
                " stats_utime_usec, " \
                " stats_stime_sec, " \
                " stats_stime_usec, " \
                " stats_real_sec, " \
                " stats_real_usec, " \
                " stats_maxrss, " \
                " stats_minflt, " \
                " stats_majflt, " \
                " stats_nswap, " \
                " stats_inblock, " \
                " stats_oublock, " \
                " stats_nvcsw, " \
                " stats_nivcsw"

static int bind_result_job_fields(struct mx_mysql_bind *result, struct mxq_job *j)
{
    int res = 0;
    int idx = 0;

    res = mx_mysql_bind_init_result(result, JOB_FIELDS_CNT);
    assert(res >= 0);

    res += mx_mysql_bind_var(result, idx++, uint64, &(j->job_id));
    res += mx_mysql_bind_var(result, idx++, uint16, &(j->job_status));
    res += mx_mysql_bind_var(result, idx++, uint64, &(j->job_flags));
    res += mx_mysql_bind_var(result, idx++, uint16, &(j->job_priority));
    res += mx_mysql_bind_var(result, idx++, uint64, &(j->group_id));
    res += mx_mysql_bind_var(result, idx++, string, &(j->job_workdir));
    res += mx_mysql_bind_var(result, idx++, uint16, &(j->job_argc));
    res += mx_mysql_bind_var(result, idx++, string, &(j->job_argv_str));
    res += mx_mysql_bind_var(result, idx++, string, &(j->job_stdout));
    res += mx_mysql_bind_var(result, idx++, string, &(j->job_stderr));
    res += mx_mysql_bind_var(result, idx++, uint32, &(j->job_umask));
    res += mx_mysql_bind_var(result, idx++, string, &(j->host_submit));
    res += mx_mysql_bind_var(result, idx++, string, &(j->host_id));
    res += mx_mysql_bind_var(result, idx++, string, &(j->server_id));
    res += mx_mysql_bind_var(result, idx++, string, &(j->host_hostname));
    res += mx_mysql_bind_var(result, idx++, uint32, &(j->host_pid));
    res += mx_mysql_bind_var(result, idx++, uint32, &(j->host_slots));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->date_submit));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->date_start));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->date_end));
    res += mx_mysql_bind_var(result, idx++, uint64, &(j->stats_max_sumrss));
    res += mx_mysql_bind_var(result, idx++,  int32, &(j->stats_status));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_utime.tv_sec));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_utime.tv_usec));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_stime.tv_sec));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_stime.tv_usec));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_realtime.tv_sec));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_realtime.tv_usec));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_maxrss));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_minflt));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_majflt));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_nswap));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_inblock));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_oublock));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_nvcsw));
    res += mx_mysql_bind_var(result, idx++,  int64, &(j->stats_rusage.ru_nivcsw));

    return res;
}

char *mxq_job_status_to_name(uint64_t status)
{
    switch (status) {
        case MXQ_JOB_STATUS_INQ:
            return "inq";
        case MXQ_JOB_STATUS_ASSIGNED:
            return "assigned";
        case MXQ_JOB_STATUS_LOADED:
            return "loaded";
        case MXQ_JOB_STATUS_RUNNING:
            return "running";
        case MXQ_JOB_STATUS_UNKNOWN_RUN:
            return "running-unknown";
        case MXQ_JOB_STATUS_EXTRUNNING:
            return "running-external";
        case MXQ_JOB_STATUS_STOPPED:
            return "stopped";
        case MXQ_JOB_STATUS_EXIT:
            return "exited";
        case MXQ_JOB_STATUS_KILLING:
            return "killing";
        case MXQ_JOB_STATUS_KILLED:
            return "killed";
        case MXQ_JOB_STATUS_FAILED:
            return "failed";
        case MXQ_JOB_STATUS_UNKNOWN_PRE:
            return "unknownpre";
        case MXQ_JOB_STATUS_CANCELLED:
            return "cancelled";
        case MXQ_JOB_STATUS_CANCELLING:
            return "cancelling";
        case MXQ_JOB_STATUS_UNKNOWN:
            return "unknown";
        case MXQ_JOB_STATUS_FINISHED:
            return "finished";
    }

    return "invalid";
}

void mxq_job_free_content(struct mxq_job *j)
{
        mx_free_null(j->job_workdir);
        mx_free_null(j->job_argv_str);
        mx_free_null(j->job_stdout);
        mx_free_null(j->job_stderr);

        if (j->tmp_stderr == j->tmp_stdout) {
            j->tmp_stdout = NULL;
        } else {
            mx_free_null(j->tmp_stdout);
        }
        mx_free_null(j->tmp_stderr);
        mx_free_null(j->host_submit);
        mx_free_null(j->host_id);
        mx_free_null(j->server_id);
        mx_free_null(j->host_hostname);
        mx_free_null(j->job_argv);
        j->job_argv = NULL;
}

int mxq_load_job(struct mx_mysql *mysql, struct mxq_job **mxq_jobs, uint64_t job_id)
{
    int res;
    struct mxq_job *jobs = NULL;
    struct mxq_job j = {0};
    struct mx_mysql_bind param = {0};
    struct mx_mysql_bind result = {0};

    assert(mysql);
    assert(mxq_jobs);
    assert(!(*mxq_jobs));

    char *query =
            "SELECT"
                JOB_FIELDS
            " FROM mxq_job"
            " WHERE job_id = ?"
            " LIMIT 1";

    res = mx_mysql_bind_init_param(&param, 1);
    assert(res == 0);

    res = mx_mysql_bind_var(&param, 0, uint64, &job_id);
    assert(res == 0);

    res = bind_result_job_fields(&result, &j);
    assert(res == 0);

    res = mx_mysql_do_statement(mysql, query, &param, &result, &j, (void **)&jobs, sizeof(*jobs));
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    *mxq_jobs = jobs;
    return res;
}

int mxq_load_jobs_in_group(struct mx_mysql *mysql, struct mxq_job **mxq_jobs, struct mxq_group *grp)
{
    int res;
    struct mxq_job *jobs = NULL;
    struct mxq_job j = {0};
    struct mx_mysql_bind param = {0};
    struct mx_mysql_bind result = {0};

    assert(mysql);
    assert(mxq_jobs);
    assert(!(*mxq_jobs));

    char *query =
            "SELECT"
                JOB_FIELDS
            " FROM mxq_job"
            " WHERE group_id = ? OR 1 = 0"
            " ORDER BY server_id, host_hostname, job_id";

    res = mx_mysql_bind_init_param(&param, 1);
    assert(res == 0);

    res = mx_mysql_bind_var(&param, 0, uint64, &(grp->group_id));
    assert(res == 0);

    res = bind_result_job_fields(&result, &j);
    assert(res == 0);

    res = mx_mysql_do_statement(mysql, query, &param, &result, &j, (void **)&jobs, sizeof(*jobs));
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    *mxq_jobs = jobs;
    return res;
}

int mxq_load_jobs_in_group_with_status(struct mx_mysql *mysql, struct mxq_job **mxq_jobs, struct mxq_group *grp, uint64_t job_status)
{
    int res;
    struct mxq_job *jobs = NULL;
    struct mxq_job j = {0};
    struct mx_mysql_bind param = {0};
    struct mx_mysql_bind result = {0};

    assert(mysql);
    assert(mxq_jobs);
    assert(!(*mxq_jobs));

    char *query =
            "SELECT"
                JOB_FIELDS
            " FROM mxq_job"
            " WHERE group_id = ?"
            "   AND job_status = ?"
            " ORDER BY server_id, host_hostname, job_id";

    res = mx_mysql_bind_init_param(&param, 2);
    assert(res == 0);

    res = 0;
    res += mx_mysql_bind_var(&param, 0, uint64, &(grp->group_id));
    res += mx_mysql_bind_var(&param, 1, uint64, &job_status);
    assert(res == 0);

    res = bind_result_job_fields(&result, &j);
    assert(res == 0);

    res = mx_mysql_do_statement(mysql, query, &param, &result, &j, (void **)&jobs, sizeof(*jobs));
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    *mxq_jobs = jobs;
    return res;
}

int mxq_assign_job_from_group_to_server(struct mx_mysql *mysql, uint64_t group_id, char *hostname, char *server_id)
{
    int res;
    struct mx_mysql_bind param = {0};

    assert(mysql);
    assert(hostname);
    assert(*hostname);
    assert(server_id);
    assert(*server_id);

    char *query =
            "UPDATE mxq_job SET"
            " job_status = " status_str(MXQ_JOB_STATUS_ASSIGNED) ","
            " host_hostname = ?,"
            " server_id = ?"
            " WHERE group_id = ?"
            " AND job_status = " status_str(MXQ_JOB_STATUS_INQ)
            " AND host_hostname = ''"
            " AND server_id = ''"
            " AND host_pid = 0"
            " ORDER BY job_priority, job_id"
            " LIMIT 1";

    res = mx_mysql_bind_init_param(&param, 3);
    assert(res == 0);

    res = 0;
    res += mx_mysql_bind_var(&param, 0, string, &hostname);
    res += mx_mysql_bind_var(&param, 1, string, &server_id);
    res += mx_mysql_bind_var(&param, 2, uint64, &group_id);
    assert(res == 0);

    res = mx_mysql_do_statement_noresult(mysql, query, &param);
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    return res;
}

int mxq_unassign_jobs_of_server(struct mx_mysql *mysql, char *hostname, char *server_id)
{
    int res;
    struct mx_mysql_bind param = {0};

    assert(mysql);
    assert(hostname);
    assert(*hostname);
    assert(server_id);
    assert(*server_id);

    char *query =
            "UPDATE mxq_job SET"
            " job_status = " status_str(MXQ_JOB_STATUS_INQ)
            " WHERE host_pid = 0"
            " AND job_status = " status_str(MXQ_JOB_STATUS_ASSIGNED)
            " AND host_hostname = ?"
            " AND server_id = ?";

    res = mx_mysql_bind_init_param(&param, 2);
    assert(res == 0);

    res = 0;
    res += mx_mysql_bind_var(&param, 0, string, &hostname);
    res += mx_mysql_bind_var(&param, 1, string, &server_id);
    assert(res == 0);

    res = mx_mysql_do_statement_noresult_retry_on_fail(mysql, query, &param);
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    return res;
}

int mxq_set_job_status_loaded_on_server(struct mx_mysql *mysql, struct mxq_job *job)
{
    int res;
    struct mx_mysql_bind param = {0};

    assert(mysql);
    assert(job);

    char *query =
            "UPDATE mxq_job SET"
            " job_status = " status_str(MXQ_JOB_STATUS_LOADED)
            ", host_id = ?"
            " WHERE job_id = ?"
            " AND job_status = " status_str(MXQ_JOB_STATUS_ASSIGNED)
            " AND host_hostname = ?"
            " AND server_id = ?"
            " AND host_pid = 0";

    res = mx_mysql_bind_init_param(&param, 4);
    assert(res == 0);

    res = 0;
    res += mx_mysql_bind_var(&param, 0, string, &(job->host_id));
    res += mx_mysql_bind_var(&param, 1, uint64, &(job->job_id));
    res += mx_mysql_bind_var(&param, 2, string, &(job->host_hostname));
    res += mx_mysql_bind_var(&param, 3, string, &(job->server_id));
    assert(res == 0);

    res = mx_mysql_do_statement_noresult_retry_on_fail(mysql, query, &param);
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    job->job_status = MXQ_JOB_STATUS_LOADED;

    return res;
}

int mxq_set_job_status_running(struct mx_mysql *mysql, struct mxq_job *job)
{
    int res;
    struct mx_mysql_bind param = {0};

    assert(mysql);
    assert(job);

    if (job->job_status != MXQ_JOB_STATUS_LOADED) {
        mx_log_warning("new status==runnning but old status(=%d) is != loaded ", job->job_status);
    }

    char *query =
            "UPDATE mxq_job SET"
            " job_status = " status_str(MXQ_JOB_STATUS_RUNNING) ","
            " date_start = NULL,"
            " host_pid = ?,"
            " host_slots = ?"
            " WHERE job_id = ?"
            " AND job_status = " status_str(MXQ_JOB_STATUS_LOADED)
            " AND host_hostname = ?"
            " AND server_id = ?"
            " AND host_pid = 0";

    res = mx_mysql_bind_init_param(&param, 5);
    assert(res == 0);

    res = 0;
    res += mx_mysql_bind_var(&param, 0, uint32, &(job->host_pid));
    res += mx_mysql_bind_var(&param, 1, uint32, &(job->host_slots));
    res += mx_mysql_bind_var(&param, 2, uint64, &(job->job_id));
    res += mx_mysql_bind_var(&param, 3, string, &(job->host_hostname));
    res += mx_mysql_bind_var(&param, 4, string, &(job->server_id));
    assert(res == 0);

    res = mx_mysql_do_statement_noresult_retry_on_fail(mysql, query, &param);
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    job->job_status = MXQ_JOB_STATUS_RUNNING;

    return res;
}

int mxq_set_job_status_exited(struct mx_mysql *mysql, struct mxq_job *job)
{
    int res;
    int idx;
    uint16_t newstatus;
    struct mx_mysql_bind param = {0};

    assert(mysql);
    assert(job);

    if (WIFEXITED(job->stats_status)) {
        if (WEXITSTATUS(job->stats_status)) {
            newstatus = MXQ_JOB_STATUS_FAILED;
        } else {
            newstatus = MXQ_JOB_STATUS_FINISHED;
        }
    } else if(WIFSIGNALED(job->stats_status)) {
        newstatus = MXQ_JOB_STATUS_KILLED;
    } else {
        mx_log_err("Status change to status_exit called with unknown stats_status (%d). Aborting Status change.", job->stats_status);
        errno = EINVAL;
        return -1;
    }

    if (job->job_status != MXQ_JOB_STATUS_RUNNING && job->job_status != MXQ_JOB_STATUS_KILLING) {
        mx_log_warning("new status==exited but old status(=%d) is != running ", job->job_status);
    }

    char *query =
            "UPDATE mxq_job SET"
            " job_status = ?,"
            " date_end = NULL,"
            " stats_max_sumrss = ?, "
            " stats_status = ?, "
            " stats_utime_sec = ?, "
            " stats_utime_usec = ?, "
            " stats_stime_sec = ?, "
            " stats_stime_usec = ?, "
            " stats_real_sec = ?, "
            " stats_real_usec = ?, "
            " stats_maxrss = ?, "
            " stats_minflt = ?, "
            " stats_majflt = ?, "
            " stats_nswap = ?, "
            " stats_inblock = ?, "
            " stats_oublock = ?, "
            " stats_nvcsw = ?, "
            " stats_nivcsw = ?"
            " WHERE job_id = ?"
            " AND job_status IN (" status_str(MXQ_JOB_STATUS_LOADED) ", " status_str(MXQ_JOB_STATUS_RUNNING) ", " status_str(MXQ_JOB_STATUS_KILLING) ")"
            " AND host_hostname = ?"
            " AND server_id = ?"
            " AND host_pid = ?";

    res = mx_mysql_bind_init_param(&param, 21);
    assert(res == 0);

    idx = 0;
    res = 0;
    res += mx_mysql_bind_var(&param, idx++, uint16, &(newstatus));
    res += mx_mysql_bind_var(&param, idx++, uint64, &(job->stats_max_sumrss));
    res += mx_mysql_bind_var(&param, idx++,  int32, &(job->stats_status));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_utime.tv_sec));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_utime.tv_usec));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_stime.tv_sec));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_stime.tv_usec));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_realtime.tv_sec));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_realtime.tv_usec));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_maxrss));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_minflt));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_majflt));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_nswap));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_inblock));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_oublock));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_nvcsw));
    res += mx_mysql_bind_var(&param, idx++,  int64, &(job->stats_rusage.ru_nivcsw));
    res += mx_mysql_bind_var(&param, idx++, uint64, &(job->job_id));
    res += mx_mysql_bind_var(&param, idx++, string, &(job->host_hostname));
    res += mx_mysql_bind_var(&param, idx++, string, &(job->server_id));
    res += mx_mysql_bind_var(&param, idx++, uint32, &(job->host_pid));
    assert(res == 0);

    res = mx_mysql_do_statement_noresult_retry_on_fail(mysql, query, &param);
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    job->job_status = newstatus;

    return res;
}

int mxq_set_job_status_unknown_for_server(struct mx_mysql *mysql, char *hostname, char *server_id)
{
    int res;
    struct mx_mysql_bind param = {0};

    assert(mysql);
    assert(hostname);
    assert(*hostname);
    assert(server_id);
    assert(*server_id);

    char *query =
            "UPDATE mxq_job SET"
            " job_status = " status_str(MXQ_JOB_STATUS_UNKNOWN) ","
            " date_end = NULL"
            " WHERE job_status IN (" status_str(MXQ_JOB_STATUS_LOADED) "," status_str(MXQ_JOB_STATUS_RUNNING) "," status_str(MXQ_JOB_STATUS_KILLING) ")"
            " AND host_hostname = ?"
            " AND server_id = ?";

    res = mx_mysql_bind_init_param(&param, 2);
    assert(res == 0);

    res = 0;
    res += mx_mysql_bind_var(&param, 0, string, &hostname);
    res += mx_mysql_bind_var(&param, 1, string, &server_id);
    assert(res == 0);

    res = mx_mysql_do_statement_noresult_retry_on_fail(mysql, query, &param);
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    return res;
}

int mxq_job_set_tmpfilenames(struct mxq_group *g, struct mxq_job *j)
{
    if (!mx_streq(j->job_stdout, "/dev/null")) {
        _mx_cleanup_free_ char *dir = NULL;

        dir = mx_dirname_forever(j->job_stdout);

        mx_asprintf_forever(&j->tmp_stdout, "%s/mxq.%u.%lu.%lu.%s.%s.%d.stdout.tmp",
            dir, g->user_uid, g->group_id, j->job_id, j->host_hostname,
            j->server_id, j->host_pid);
    }

    if (!mx_streq(j->job_stderr, "/dev/null")) {
        _mx_cleanup_free_ char *dir = NULL;

        if (mx_streq(j->job_stderr, j->job_stdout)) {
            j->tmp_stderr = j->tmp_stdout;
            return 1;
        }
        dir = mx_dirname_forever(j->job_stderr);

        mx_asprintf_forever(&j->tmp_stderr, "%s/mxq.%u.%lu.%lu.%s.%s.%d.stderr.tmp",
            dir, g->user_uid, g->group_id, j->job_id, j->host_hostname,
            j->server_id, j->host_pid);
    }
    return 1;
}

int mxq_load_job_from_group_assigned_to_server(struct mx_mysql *mysql, struct mxq_job **mxq_jobs, uint64_t group_id, char *hostname, char *server_id)
{
    int res;
    struct mxq_job *jobs = NULL;
    struct mxq_job j = {0};
    struct mx_mysql_bind param = {0};
    struct mx_mysql_bind result = {0};

    assert(mysql);
    assert(mxq_jobs);
    assert(!(*mxq_jobs));
    assert(hostname);
    assert(*hostname);
    assert(server_id);
    assert(*server_id);

    char *query =
            "SELECT"
                JOB_FIELDS
            " FROM mxq_job"
            " WHERE job_status = " status_str(MXQ_JOB_STATUS_ASSIGNED)
            " AND host_hostname = ?"
            " AND server_id  = ?"
            " AND group_id = ?"
            " LIMIT 1";

    res = mx_mysql_bind_init_param(&param, 3);
    assert(res == 0);

    res = 0;
    res += mx_mysql_bind_var(&param, 0, string, &hostname);
    res += mx_mysql_bind_var(&param, 1, string, &server_id);
    res += mx_mysql_bind_var(&param, 2, uint64, &group_id);
    assert(res == 0);

    res = bind_result_job_fields(&result, &j);
    assert(res == 0);

    res = mx_mysql_do_statement(mysql, query, &param, &result, &j, (void **)&jobs, sizeof(*jobs));
    if (res < 0) {
        mx_log_err("mx_mysql_do_statement(): %m");
        return res;
    }

    *mxq_jobs = jobs;
    return res;
}

int mxq_load_job_from_group_for_server(struct mx_mysql *mysql, struct mxq_job *mxqjob, uint64_t group_id, char *hostname, char *server_id, char *host_id)
{
    int res;
    struct mxq_job *jobs   = NULL;

    assert(mysql);
    assert(mxqjob);
    assert(hostname);
    assert(*hostname);
    assert(server_id);
    assert(*server_id);
    assert(host_id);
    assert(*host_id);

    do {
        res = mxq_load_job_from_group_assigned_to_server(mysql, &jobs, group_id, hostname, server_id);

        if(res < 0) {
            mx_log_err("  group_id=%lu :: mxq_load_job_from_group_assigned_to_server: %m", group_id);
            return 0;
        }
        if(res == 1) {
            memcpy(mxqjob, &jobs[0], sizeof(*mxqjob));
            free(jobs);
            break;
        }

        res = mxq_assign_job_from_group_to_server(mysql, group_id, hostname, server_id);
        if (res < 0) {
            mx_log_err("  group_id=%lu :: mxq_assign_job_from_group_to_server(): %m", group_id);
            return 0;
        }
        if (res == 0) {
            mx_log_warning("  group_id=%lu :: mxq_assign_job_from_group_to_server(): No matching job found - maybe another server was a bit faster. ;)", group_id);
            return 0;
        }
    } while (1);

    mx_free_null(mxqjob->host_id);
    mxqjob->host_id = mx_strdup_forever(host_id);

    res = mxq_set_job_status_loaded_on_server(mysql, mxqjob);
    if (res < 0) {
        mx_log_err("  group_id=%lu job_id=%lu :: mxq_set_job_status_loaded_on_server(): %m", group_id, mxqjob->job_id);
        return 0;
    }
    if (res == 0) {
        mx_log_err("  group_id=%lu job_id=%lu :: mxq_set_job_status_loaded_on_server(): Job not found", group_id, mxqjob->job_id);
        return 0;
    }

    mxqjob->job_status = MXQ_JOB_STATUS_LOADED;

    return 1;
}