don't delay loading master even if messages were expired

the delay optimized the corner case of previously important but now
expired messages on the slave disappearing, either through an external
expunge or after a journal replay. no point in pessimizing the common
case.
This commit is contained in:
Oswald Buddenhagen 2013-11-17 11:23:44 +01:00
parent 12676f28da
commit 273ac899f3

View File

@ -100,7 +100,6 @@ make_flags( int flags, char *buf )
#define S_EXPIRED (1<<4) /* the entry is expired (slave message removal confirmed) */
#define S_EXPIRE (1<<5) /* the entry is being expired (slave message removal scheduled) */
#define S_NEXPIRE (1<<6) /* temporary: new expiration state */
#define S_EXP_S (1<<7) /* temporary: expired slave message is actually gone */
#define mvBit(in,ib,ob) ((unsigned char)(((unsigned)in) * (ob) / (ib)))
@ -653,6 +652,7 @@ box_selected( int sts, void *aux )
channel_conf_t *chan;
FILE *jfp;
int opts[2], line, t1, t2, t3;
int *mexcs, nmexcs, rmexcs, minwuid;
struct stat st;
struct flock lck;
char fbuf[16]; /* enlarge when support for keywords is added */
@ -1010,7 +1010,63 @@ box_selected( int sts, void *aux )
svars->drv[M]->prepare_opts( ctx[M], opts[M] );
svars->drv[S]->prepare_opts( ctx[S], opts[S] );
if (!svars->smaxxuid && load_box( svars, M, (ctx[M]->opts & OPEN_OLD) ? 1 : INT_MAX, 0, 0 ))
mexcs = 0;
nmexcs = rmexcs = 0;
if (svars->ctx[M]->opts & OPEN_OLD) {
if (svars->smaxxuid) {
/* When messages have been expired on the slave, the master fetch is split into
* two ranges: The bulk fetch which corresponds with the most recent messages, and an
* exception list of messages which would have been expired if they weren't important. */
debug( "preparing master selection - max expired slave uid is %d\n", svars->smaxxuid );
/* First, find out the lower bound for the bulk fetch. */
minwuid = INT_MAX;
for (srec = svars->srecs; srec; srec = srec->next) {
if (srec->status & S_DEAD)
continue;
if (srec->status & S_EXPIRED) {
if (!srec->uid[S]) {
/* The expired message was already gone. */
continue;
}
/* The expired message was not expunged yet, so re-examine it.
* This will happen en masse, so just extend the bulk fetch. */
} else {
if (svars->smaxxuid >= srec->uid[S]) {
/* The non-expired message is in the generally expired range, so don't
* make it contribute to the bulk fetch. */
continue;
}
/* Usual non-expired message. */
}
if (minwuid > srec->uid[M])
minwuid = srec->uid[M];
}
debug( " min non-orphaned master uid is %d\n", minwuid );
/* Next, calculate the exception fetch. */
for (srec = svars->srecs; srec; srec = srec->next) {
if (srec->status & S_DEAD)
continue;
if (srec->uid[M] > 0 && srec->uid[S] > 0 && minwuid > srec->uid[M] &&
(!(svars->ctx[M]->opts & OPEN_NEW) || svars->maxuid[M] >= srec->uid[M])) {
/* The pair is alive, but outside the bulk range. */
if (nmexcs == rmexcs) {
rmexcs = rmexcs * 2 + 100;
mexcs = nfrealloc( mexcs, rmexcs * sizeof(int) );
}
mexcs[nmexcs++] = srec->uid[M];
}
}
debugn( " exception list is:" );
for (t = 0; t < nmexcs; t++)
debugn( " %d", mexcs[t] );
debug( "\n" );
} else {
minwuid = 1;
}
} else {
minwuid = INT_MAX;
}
if (load_box( svars, M, minwuid, mexcs, nmexcs ))
return;
load_box( svars, S, (ctx[S]->opts & OPEN_OLD) ? 1 : INT_MAX, 0, 0 );
}
@ -1067,7 +1123,7 @@ box_loaded( int sts, void *aux )
message_t *tmsg;
copy_vars_t *cv;
flag_vars_t *fv;
int uid, minwuid, *mexcs, nmexcs, rmexcs, no[2], del[2], alive, todel, t1, t2;
int uid, no[2], del[2], alive, todel, t1, t2;
int sflags, nflags, aflags, dflags, nex;
unsigned hashsz, idx;
char fbuf[16]; /* enlarge when support for keywords is added */
@ -1123,64 +1179,6 @@ box_loaded( int sts, void *aux )
}
free( srecmap );
if ((t == S) && svars->smaxxuid) {
/* When messages have been expired on the slave, the master fetch is split into
* two ranges: The bulk fetch which corresponds with the most recent messages, and an
* exception list of messages which would have been expired if they weren't important. */
debug( "preparing master selection - max expired slave uid is %d\n", svars->smaxxuid );
/* First, find out the lower bound for the bulk fetch.
* On the way, mark successfully expired messages. */
minwuid = INT_MAX;
for (srec = svars->srecs; srec; srec = srec->next) {
if (srec->status & S_DEAD)
continue;
if (srec->status & S_EXPIRED) {
if (!srec->uid[S] || ((svars->ctx[S]->opts & OPEN_OLD) && !srec->msg[S])) {
/* The expired message was already gone or it is gone now. */
srec->status |= S_EXP_S;
continue;
}
/* The expired message was not expunged yet, so re-examine it.
* This will happen en masse, so just extend the bulk fetch. */
} else {
if (svars->smaxxuid >= srec->uid[S]) {
/* The non-expired message is in the generally expired range, so don't
* make it contribute to the bulk fetch. */
continue;
}
/* Usual non-expired message. */
}
if (minwuid > srec->uid[M])
minwuid = srec->uid[M];
}
debug( " min non-orphaned master uid is %d\n", minwuid );
/* Next, calculate the exception fetch. */
mexcs = 0;
nmexcs = rmexcs = 0;
if (svars->ctx[M]->opts & OPEN_OLD) {
for (srec = svars->srecs; srec; srec = srec->next) {
if (srec->status & S_DEAD)
continue;
if (srec->uid[M] > 0 && srec->uid[S] > 0 &&
!(srec->status & S_EXP_S) && minwuid > srec->uid[M] &&
(!(svars->ctx[M]->opts & OPEN_NEW) || svars->maxuid[M] >= srec->uid[M])) {
/* The pair is alive, but outside the bulk range. */
if (nmexcs == rmexcs) {
rmexcs = rmexcs * 2 + 100;
mexcs = nfrealloc( mexcs, rmexcs * sizeof(int) );
}
mexcs[nmexcs++] = srec->uid[M];
}
}
}
debugn( " exception list is:" );
for (t = 0; t < nmexcs; t++)
debugn( " %d", mexcs[t] );
debug( "\n" );
load_box( svars, M, minwuid, mexcs, nmexcs );
return;
}
if (!(svars->state[1-t] & ST_LOADED))
return;