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authorBruce Momjian <bruce@momjian.us>2014-05-06 11:26:28 -0400
committerBruce Momjian <bruce@momjian.us>2014-05-06 11:26:28 -0400
commit04e15c69d2176849aad40dc8df55761ba0ad0491 (patch)
treeb35274c9d4f7beaa41f6850977cd41024ce36dfa /src/backend/access/transam/multixact.c
parent41fdcf71d2b424104e08ce229104b8e8e2840d1b (diff)
Remove tabs after spaces in C comments
This was not changed in HEAD, but will be done later as part of a pgindent run. Future pgindent runs will also do this. Report by Tom Lane Backpatch through all supported branches, but not HEAD
Diffstat (limited to 'src/backend/access/transam/multixact.c')
-rw-r--r--src/backend/access/transam/multixact.c56
1 files changed, 28 insertions, 28 deletions
diff --git a/src/backend/access/transam/multixact.c b/src/backend/access/transam/multixact.c
index bacdbd64eff..8886ce4c672 100644
--- a/src/backend/access/transam/multixact.c
+++ b/src/backend/access/transam/multixact.c
@@ -5,7 +5,7 @@
*
* The pg_multixact manager is a pg_clog-like manager that stores an array of
* MultiXactMember for each MultiXactId. It is a fundamental part of the
- * shared-row-lock implementation. Each MultiXactMember is comprised of a
+ * shared-row-lock implementation. Each MultiXactMember is comprised of a
* TransactionId and a set of flag bits. The name is a bit historical:
* originally, a MultiXactId consisted of more than one TransactionId (except
* in rare corner cases), hence "multi". Nowadays, however, it's perfectly
@@ -18,7 +18,7 @@
*
* We use two SLRU areas, one for storing the offsets at which the data
* starts for each MultiXactId in the other one. This trick allows us to
- * store variable length arrays of TransactionIds. (We could alternatively
+ * store variable length arrays of TransactionIds. (We could alternatively
* use one area containing counts and TransactionIds, with valid MultiXactId
* values pointing at slots containing counts; but that way seems less robust
* since it would get completely confused if someone inquired about a bogus
@@ -38,7 +38,7 @@
*
* Like clog.c, and unlike subtrans.c, we have to preserve state across
* crashes and ensure that MXID and offset numbering increases monotonically
- * across a crash. We do this in the same way as it's done for transaction
+ * across a crash. We do this in the same way as it's done for transaction
* IDs: the WAL record is guaranteed to contain evidence of every MXID we
* could need to worry about, and we just make sure that at the end of
* replay, the next-MXID and next-offset counters are at least as large as
@@ -50,7 +50,7 @@
* The minimum value in each database is stored in pg_database, and the
* global minimum is part of pg_control. Any vacuum that is able to
* advance its database's minimum value also computes a new global minimum,
- * and uses this value to truncate older segments. When new multixactid
+ * and uses this value to truncate older segments. When new multixactid
* values are to be created, care is taken that the counter does not
* fall within the wraparound horizon considering the global minimum value.
*
@@ -85,13 +85,13 @@
/*
- * Defines for MultiXactOffset page sizes. A page is the same BLCKSZ as is
+ * Defines for MultiXactOffset page sizes. A page is the same BLCKSZ as is
* used everywhere else in Postgres.
*
* Note: because MultiXactOffsets are 32 bits and wrap around at 0xFFFFFFFF,
* MultiXact page numbering also wraps around at
* 0xFFFFFFFF/MULTIXACT_OFFSETS_PER_PAGE, and segment numbering at
- * 0xFFFFFFFF/MULTIXACT_OFFSETS_PER_PAGE/SLRU_SEGMENTS_PER_PAGE. We need
+ * 0xFFFFFFFF/MULTIXACT_OFFSETS_PER_PAGE/SLRU_SEGMENTS_PER_PAGE. We need
* take no explicit notice of that fact in this module, except when comparing
* segment and page numbers in TruncateMultiXact (see
* MultiXactOffsetPagePrecedes).
@@ -110,7 +110,7 @@
* additional flag bits for each TransactionId. To do this without getting
* into alignment issues, we store four bytes of flags, and then the
* corresponding 4 Xids. Each such 5-word (20-byte) set we call a "group", and
- * are stored as a whole in pages. Thus, with 8kB BLCKSZ, we keep 409 groups
+ * are stored as a whole in pages. Thus, with 8kB BLCKSZ, we keep 409 groups
* per page. This wastes 12 bytes per page, but that's OK -- simplicity (and
* performance) trumps space efficiency here.
*
@@ -161,7 +161,7 @@ static SlruCtlData MultiXactMemberCtlData;
#define MultiXactMemberCtl (&MultiXactMemberCtlData)
/*
- * MultiXact state shared across all backends. All this state is protected
+ * MultiXact state shared across all backends. All this state is protected
* by MultiXactGenLock. (We also use MultiXactOffsetControlLock and
* MultiXactMemberControlLock to guard accesses to the two sets of SLRU
* buffers. For concurrency's sake, we avoid holding more than one of these
@@ -179,7 +179,7 @@ typedef struct MultiXactStateData
MultiXactId lastTruncationPoint;
/*
- * oldest multixact that is still on disk. Anything older than this
+ * oldest multixact that is still on disk. Anything older than this
* should not be consulted.
*/
MultiXactId oldestMultiXactId;
@@ -528,7 +528,7 @@ MultiXactIdIsRunning(MultiXactId multi)
/*
* This could be made faster by having another entry point in procarray.c,
- * walking the PGPROC array only once for all the members. But in most
+ * walking the PGPROC array only once for all the members. But in most
* cases nmembers should be small enough that it doesn't much matter.
*/
for (i = 0; i < nmembers; i++)
@@ -615,7 +615,7 @@ MultiXactIdSetOldestMember(void)
* The value to set is the oldest of nextMXact and all the valid per-backend
* OldestMemberMXactId[] entries. Because of the locking we do, we can be
* certain that no subsequent call to MultiXactIdSetOldestMember can set
- * an OldestMemberMXactId[] entry older than what we compute here. Therefore
+ * an OldestMemberMXactId[] entry older than what we compute here. Therefore
* there is no live transaction, now or later, that can be a member of any
* MultiXactId older than the OldestVisibleMXactId we compute here.
*/
@@ -751,7 +751,7 @@ MultiXactIdCreateFromMembers(int nmembers, MultiXactMember *members)
* heap_lock_tuple() to have put it there, and heap_lock_tuple() generates
* an XLOG record that must follow ours. The normal LSN interlock between
* the data page and that XLOG record will ensure that our XLOG record
- * reaches disk first. If the SLRU members/offsets data reaches disk
+ * reaches disk first. If the SLRU members/offsets data reaches disk
* sooner than the XLOG record, we do not care because we'll overwrite it
* with zeroes unless the XLOG record is there too; see notes at top of
* this file.
@@ -882,7 +882,7 @@ RecordNewMultiXact(MultiXactId multi, MultiXactOffset offset,
* GetNewMultiXactId
* Get the next MultiXactId.
*
- * Also, reserve the needed amount of space in the "members" area. The
+ * Also, reserve the needed amount of space in the "members" area. The
* starting offset of the reserved space is returned in *offset.
*
* This may generate XLOG records for expansion of the offsets and/or members
@@ -916,7 +916,7 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
/*----------
* Check to see if it's safe to assign another MultiXactId. This protects
- * against catastrophic data loss due to multixact wraparound. The basic
+ * against catastrophic data loss due to multixact wraparound. The basic
* rules are:
*
* If we're past multiVacLimit, start trying to force autovacuum cycles.
@@ -930,7 +930,7 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
{
/*
* For safety's sake, we release MultiXactGenLock while sending
- * signals, warnings, etc. This is not so much because we care about
+ * signals, warnings, etc. This is not so much because we care about
* preserving concurrency in this situation, as to avoid any
* possibility of deadlock while doing get_database_name(). First,
* copy all the shared values we'll need in this path.
@@ -1036,7 +1036,7 @@ GetNewMultiXactId(int nmembers, MultiXactOffset *offset)
* until after file extension has succeeded!
*
* We don't care about MultiXactId wraparound here; it will be handled by
- * the next iteration. But note that nextMXact may be InvalidMultiXactId
+ * the next iteration. But note that nextMXact may be InvalidMultiXactId
* or the first value on a segment-beginning page after this routine
* exits, so anyone else looking at the variable must be prepared to deal
* with either case. Similarly, nextOffset may be zero, but we won't use
@@ -1114,16 +1114,16 @@ GetMultiXactIdMembers(MultiXactId multi, MultiXactMember **members,
* need to allow an empty set to be returned regardless, if the caller is
* willing to accept it; the caller is expected to check that it's an
* allowed condition (such as ensuring that the infomask bits set on the
- * tuple are consistent with the pg_upgrade scenario). If the caller is
+ * tuple are consistent with the pg_upgrade scenario). If the caller is
* expecting this to be called only on recently created multis, then we
* raise an error.
*
* Conversely, an ID >= nextMXact shouldn't ever be seen here; if it is
- * seen, it implies undetected ID wraparound has occurred. This raises a
+ * seen, it implies undetected ID wraparound has occurred. This raises a
* hard error.
*
* Shared lock is enough here since we aren't modifying any global state.
- * Acquire it just long enough to grab the current counter values. We may
+ * Acquire it just long enough to grab the current counter values. We may
* need both nextMXact and nextOffset; see below.
*/
LWLockAcquire(MultiXactGenLock, LW_SHARED);
@@ -1151,12 +1151,12 @@ GetMultiXactIdMembers(MultiXactId multi, MultiXactMember **members,
/*
* Find out the offset at which we need to start reading MultiXactMembers
- * and the number of members in the multixact. We determine the latter as
+ * and the number of members in the multixact. We determine the latter as
* the difference between this multixact's starting offset and the next
* one's. However, there are some corner cases to worry about:
*
* 1. This multixact may be the latest one created, in which case there is
- * no next one to look at. In this case the nextOffset value we just
+ * no next one to look at. In this case the nextOffset value we just
* saved is the correct endpoint.
*
* 2. The next multixact may still be in process of being filled in: that
@@ -1167,11 +1167,11 @@ GetMultiXactIdMembers(MultiXactId multi, MultiXactMember **members,
* (because we are careful to pre-zero offset pages). Because
* GetNewMultiXactId will never return zero as the starting offset for a
* multixact, when we read zero as the next multixact's offset, we know we
- * have this case. We sleep for a bit and try again.
+ * have this case. We sleep for a bit and try again.
*
* 3. Because GetNewMultiXactId increments offset zero to offset one to
* handle case #2, there is an ambiguity near the point of offset
- * wraparound. If we see next multixact's offset is one, is that our
+ * wraparound. If we see next multixact's offset is one, is that our
* multixact's actual endpoint, or did it end at zero with a subsequent
* increment? We handle this using the knowledge that if the zero'th
* member slot wasn't filled, it'll contain zero, and zero isn't a valid
@@ -1694,7 +1694,7 @@ multixact_twophase_postabort(TransactionId xid, uint16 info,
/*
* Initialization of shared memory for MultiXact. We use two SLRU areas,
- * thus double memory. Also, reserve space for the shared MultiXactState
+ * thus double memory. Also, reserve space for the shared MultiXactState
* struct and the per-backend MultiXactId arrays (two of those, too).
*/
Size
@@ -1754,7 +1754,7 @@ MultiXactShmemInit(void)
/*
* This func must be called ONCE on system install. It creates the initial
- * MultiXact segments. (The MultiXacts directories are assumed to have been
+ * MultiXact segments. (The MultiXacts directories are assumed to have been
* created by initdb, and MultiXactShmemInit must have been called already.)
*/
void
@@ -1925,7 +1925,7 @@ TrimMultiXact(void)
MultiXactOffsetCtl->shared->latest_page_number = pageno;
/*
- * Zero out the remainder of the current offsets page. See notes in
+ * Zero out the remainder of the current offsets page. See notes in
* StartupCLOG() for motivation.
*/
entryno = MultiXactIdToOffsetEntry(multi);
@@ -1955,7 +1955,7 @@ TrimMultiXact(void)
MultiXactMemberCtl->shared->latest_page_number = pageno;
/*
- * Zero out the remainder of the current members page. See notes in
+ * Zero out the remainder of the current members page. See notes in
* TrimCLOG() for motivation.
*/
flagsoff = MXOffsetToFlagsOffset(offset);
@@ -2097,7 +2097,7 @@ SetMultiXactIdLimit(MultiXactId oldest_datminmxid, Oid oldest_datoid)
/*
* We'll start complaining loudly when we get within 10M multis of the
- * stop point. This is kind of arbitrary, but if you let your gas gauge
+ * stop point. This is kind of arbitrary, but if you let your gas gauge
* get down to 1% of full, would you be looking for the next gas station?
* We need to be fairly liberal about this number because there are lots
* of scenarios where most transactions are done by automatic clients that