Commit daf4c11f authored by Nick Mathewson's avatar Nick Mathewson 🦀
Browse files

r15630@catbus: nickm | 2007-10-10 13:39:44 -0400 

 Save weighted-fractional-uptime to disk as well as MTBF.  Bump the version on rouer-stability: downgrading to versions earlier than this one will lose your WFU data.


svn:r11835
parent 1a94e846

ChangeLog

+6 −0
Original line number Diff line number Diff line
@@ -2,6 +2,12 @@ Changes in version 0.2.0.8-alpha - 2007-??-?? 
  o Major features (directory authorities):

    - When an authority is missing votes or signatures, it now tries to fetch

      them.

    - Directory authorities track weighted fractional uptime as well as

      weighted mean-time-between failures.  WFU is suitable for deciding

      whether a node is "usually up", while MTBF is suitable for deciding

      whether a node is "likely to stay up."  We need both, because "usually

      up" is a good requirement for guards, while "likely to stay up" is

      a good requirement for long-lived connections.



  o Major features (v3 directory system):

    - Caches now download v3 network status documents as needed.

src/or/rephist.c

+127 −28
Original line number Diff line number Diff line
@@ -641,7 +641,7 @@ rep_hist_record_mtbf_data(void) 
#define PUT(s) STMT_BEGIN if (fputs((s),f)<0) goto err; STMT_END

#define PRINTF(args) STMT_BEGIN if (fprintf args <0) goto err; STMT_END



  PUT("format 1\n");

  PUT("format 2\n");



  format_iso_time(time_buf, time(NULL));

  PRINTF((f, "stored-at %s\n", time_buf));
@@ -666,12 +666,21 @@ rep_hist_record_mtbf_data(void) 
    hist = (or_history_t*) or_history_p;



    base16_encode(dbuf, sizeof(dbuf), digest, DIGEST_LEN);

    PRINTF((f, "R %s\n", dbuf));

    if (hist->start_of_run) {

      format_iso_time(time_buf, hist->start_of_run);

      t = time_buf;

    }

    PRINTF((f, "%s %lu %.5lf%s%s\n",

            dbuf, hist->weighted_run_length, hist->total_run_weights,

    PRINTF((f, "+MTBF %lu %.5lf%s%s\n",

            hist->weighted_run_length, hist->total_run_weights,

            t ? " S=" : "", t ? t : ""));

    t = NULL;

    if (hist->start_of_downtime) {

      format_iso_time(time_buf, hist->start_of_downtime);

      t = time_buf;

    }

    PRINTF((f, "+WFU %lu %lu%s%s\n",

            hist->weighted_uptime, hist->total_weighted_time,

            t ? " S=" : "", t ? t : ""));

  }
@@ -686,6 +695,22 @@ rep_hist_record_mtbf_data(void) 
  return -1;

}



/** Helper: return the first j >= i such that !strcmpstart(sl[j], prefix) and

 * such that no line sl[k] with i <= k < j starts with "R ".  Return -1 if no

 * such line exists. */

static int

find_next_with(smartlist_t *sl, int i, const char *prefix)

{

  for ( ; i < smartlist_len(sl); ++i) {

    const char *line = smartlist_get(sl, i);

    if (!strcmpstart(line, prefix))

      return i;

    if (!strcmpstart(line, "R "))

      return -1;

  }

  return -1;

}



/** Load MTBF data from disk.  Returns 0 on success or recoverable error, -1

 * on failure. */

int
@@ -697,6 +722,7 @@ rep_hist_load_mtbf_data(time_t now) 
  int r=0, i;

  time_t last_downrated = 0, stored_at = 0, tracked_since = 0;

  time_t latest_possible_start = now;

  long format = -1;



  {

    char *filename = get_mtbf_filename();
@@ -709,8 +735,18 @@ rep_hist_load_mtbf_data(time_t now) 
    tor_free(d);

  }



  if (smartlist_len(lines)<4 || strcmp(smartlist_get(lines, 0), "format 1")) {

    log_warn(LD_GENERAL,"Unrecognized format in mtbf history file. Skipping.");

  {

    const char *firstline;

    if (smartlist_len(lines)>4) {

      firstline = smartlist_get(lines, 0);

      if (!strcmpstart(firstline, "format "))

        format = tor_parse_long(firstline+strlen("format "),

                                10, -1, LONG_MAX, NULL, NULL);

    }

  }

  if (format != 1 && format != 2) {

    log_warn(LD_GENERAL,

             "Unrecognized format in mtbf history file. Skipping.");

    goto err;

  }

  for (i = 1; i < smartlist_len(lines); ++i) {
@@ -749,35 +785,82 @@ rep_hist_load_mtbf_data(time_t now) 
  for (; i < smartlist_len(lines); ++i) {

    char digest[DIGEST_LEN];

    char hexbuf[HEX_DIGEST_LEN+1];

    char timebuf[ISO_TIME_LEN+1];

    char mtbf_timebuf[ISO_TIME_LEN+1];

    char wfu_timebuf[ISO_TIME_LEN+1];

    time_t start_of_run = 0;

    long wrl;

    double trw;

    time_t start_of_downtime = 0;

    int have_mtbf = 0, have_wfu = 0;

    long wrl = 0;

    double trw = 0;

    long wt_uptime = 0, total_wt_time = 0;

    int n;

    or_history_t *hist;

    line = smartlist_get(lines, i);

    if (!strcmp(line, "."))

      break;



    mtbf_timebuf[0] = '\0';

    wfu_timebuf[0] = '\0';



    if (format == 1) {

      /* XXXX020 audit the heck out of my scanf usage. */

      n = sscanf(line, "%40s %ld %lf S=%10s %8s",

               hexbuf, &wrl, &trw, timebuf, timebuf+11);

                 hexbuf, &wrl, &trw, mtbf_timebuf, mtbf_timebuf+11);

      if (n != 3 && n != 5) {

        log_warn(LD_GENERAL, "Couldn't scan line %s", escaped(line));

        continue;

      }

      have_mtbf = 1;

    } else {

      // format == 2.

      int mtbf_idx, wfu_idx;

      if (strcmpstart(line, "R ") || strlen(line) < 2+HEX_DIGEST_LEN)

        continue;

      strlcpy(hexbuf, line+2, sizeof(hexbuf));

      mtbf_idx = find_next_with(lines, i+1, "+MTBF ");

      wfu_idx = find_next_with(lines, i+1, "+WFU ");

      if (mtbf_idx >= 0) {

        const char *mtbfline = smartlist_get(lines, mtbf_idx);

        n = sscanf(mtbfline, "+MTBF %lu %lf S=%10s %8s",

                   &wrl, &trw, mtbf_timebuf, mtbf_timebuf+11);

        if (n == 2 || n == 4) {

          have_mtbf = 1;

        } else {

          log_warn(LD_GENERAL, "Couldn't scan +MTBF line %s",

                   escaped(mtbfline));

        }

      }

      if (wfu_idx >= 0) {

        const char *wfuline = smartlist_get(lines, wfu_idx);

        n = sscanf(wfuline, "+WFU %lu %lu S=%10s %8s",

                   &wt_uptime, &total_wt_time,

                   wfu_timebuf, wfu_timebuf+11);

        if (n == 2 || n == 4) {

          have_wfu = 1;

        } else {

          log_warn(LD_GENERAL, "Couldn't scan +WFU line %s", escaped(wfuline));

        }

      }

      if (wfu_idx > i)

        i = wfu_idx;

      if (mtbf_idx > i)

        i = mtbf_idx;

    }

    if (base16_decode(digest, DIGEST_LEN, hexbuf, HEX_DIGEST_LEN) < 0) {

      log_warn(LD_GENERAL, "Couldn't hex string %s", escaped(hexbuf));

      continue;

    }

    if (n == 5) {

      timebuf[10] = ' ';

      if (parse_iso_time(timebuf, &start_of_run)<0)

        log_warn(LD_GENERAL, "Couldn't parse time %s", escaped(timebuf));

    }

    hist = get_or_history(digest);

    if (!hist)

      continue;



    if (have_mtbf) {

      if (mtbf_timebuf[0]) {

        mtbf_timebuf[10] = ' ';

        if (parse_iso_time(mtbf_timebuf, &start_of_run)<0)

          log_warn(LD_GENERAL, "Couldn't parse time %s",

                   escaped(mtbf_timebuf));

      }

      if (!start_of_run || start_of_run > stored_at) {

        hist->start_of_run = 0;

      } else {
@@ -790,6 +873,22 @@ rep_hist_load_mtbf_data(time_t now) 
      hist->weighted_run_length = wrl;

      hist->total_run_weights = trw;

    }

    if (have_wfu) {

      if (wfu_timebuf[0]) {

        wfu_timebuf[10] = ' ';

        if (parse_iso_time(wfu_timebuf, &start_of_downtime)<0)

          log_warn(LD_GENERAL, "Couldn't parse time %s", escaped(wfu_timebuf));

      }

    }

    if (!start_of_downtime || start_of_downtime > stored_at) {

      hist->start_of_downtime = 0;

    } else {

      long down_length = stored_at - start_of_downtime;

      hist->start_of_downtime = start_of_downtime - down_length;

    }

    hist->weighted_uptime = wt_uptime;

    hist->total_weighted_time = total_wt_time;

  }

  if (strcmp(line, "."))

    log_warn(LD_GENERAL, "Truncated MTBF file.");