/*
* calculate size of (one fork of) a relation
*
* Iterator over all files belong to the relation and do stat.
* The obviously better way is to use glob. For whatever reason,
* glob is extremely slow if there are lots of relations in the
* database. So we handle all cases, instead.
*
* Note: we can safely apply this to temp tables of other sessions, so there
* is no check here or at the call sites for that.
*/
static int64
calculate_relation_size(Relation rel, ForkNumber forknum)
{
int64 totalsize = 0;
char *relationpath;
char pathname[MAXPGPATH];
unsigned int segcount = 0;
relationpath = relpathbackend(rel->rd_node, rel->rd_backend, forknum);
if (RelationIsHeap(rel))
{
/* Ordinary relation, including heap and index.
* They take form of relationpath, or relationpath.%d
* There will be no holes, therefore, we can stop when
* we reach the first non-existing file.
*/
for (segcount = 0;; segcount++)
{
struct stat fst;
CHECK_FOR_INTERRUPTS();
if (segcount == 0)
snprintf(pathname, MAXPGPATH, "%s",
relationpath);
else
snprintf(pathname, MAXPGPATH, "%s.%u",
relationpath, segcount);
if (stat(pathname, &fst) < 0)
{
if (errno == ENOENT)
break;
else
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not stat file %s: %m", pathname)));
}
totalsize += fst.st_size;
}
}
/* AO tables don't have any extra forks. */
else if (forknum == MAIN_FORKNUM)
{
if (RelationIsAoRows(rel))
{
totalsize = GetAOTotalBytes(rel, GetActiveSnapshot());
}
else if (RelationIsAoCols(rel))
{
totalsize = GetAOCSTotalBytes(rel, GetActiveSnapshot(), true);
}
}
/* RELSTORAGE_VIRTUAL has no space usage */
return totalsize;
}
/*
* calculate size of a relation
*
* Iterator over all files belong to the relation and do stat.
* The obviously better way is to use glob. For whatever reason,
* glob is extremely slow if there are lots of relations in the
* database. So we handle all cases, instead.
*/
static int64
calculate_relation_size(Relation rel)
{
int64 totalsize = 0;
char *relationpath;
char pathname[MAXPGPATH];
struct stat fst;
int i;
relationpath = relpath(rel->rd_node);
if(RelationIsHeap(rel))
{
/* Ordinary relation, including heap and index.
* They take form of relationpath, or relationpath.%d
* There will be no holes, therefore, we can stop we
* we reach the first non-exist file.
*/
for(i=0; ; ++i)
{
if (i==0)
snprintf(pathname, MAXPGPATH, "%s", relationpath);
else
snprintf(pathname, MAXPGPATH, "%s.%d", relationpath, i);
if (stat(pathname, &fst) >= 0)
totalsize += fst.st_size;
else
{
if (errno == ENOENT)
break;
else
ereport(ERROR, (errcode_for_file_access(),
errmsg("could not stat file %s: %m", pathname)
));
}
}
}
else if (RelationIsAoRows(rel))
totalsize = GetAOTotalBytes(rel, SnapshotNow);
else if (RelationIsAoCols(rel))
totalsize = GetAOCSTotalBytes(rel, SnapshotNow);
/* RELSTORAGE_VIRTUAL has no space usage */
return totalsize;
}
