Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commitc715fde

Browse files
committed
Significant cleanups in SysV IPC handling (shared mem and semaphores).
IPC key assignment will now work correctly even when multiple postmastersare using same logical port number (which is possible given -k switch).There is only one shared-mem segment per postmaster now, not 3.Rip out broken code for non-TAS case in bufmgr and xlog, substitute acomplete S_LOCK emulation using semaphores in spin.c. TAS and non-TASlogic is now exactly the same.When deadlock is detected, "Deadlock detected" is now the elog(ERROR)message, rather than a NOTICE that comes out before an unhelpful ERROR.
1 parent9148227 commitc715fde

File tree

27 files changed

+1145
-1728
lines changed

27 files changed

+1145
-1728
lines changed

‎doc/src/sgml/ref/postmaster.sgml

Lines changed: 1 addition & 27 deletions
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
<!--
2-
$Header: /cvsroot/pgsql/doc/src/sgml/ref/postmaster.sgml,v 1.16 2000/11/22 01:41:13 momjian Exp $
2+
$Header: /cvsroot/pgsql/doc/src/sgml/ref/postmaster.sgml,v 1.17 2000/11/28 23:27:54 tgl Exp $
33
Postgres documentation
44
-->
55

@@ -400,32 +400,6 @@ $ ps -e | grep postmast
400400
</para>
401401
</listitem>
402402
</varlistentry>
403-
404-
<varlistentry>
405-
<term><computeroutput>
406-
IpcMemoryAttach: shmat() failed: Permission denied
407-
</computeroutput></term>
408-
<listitem>
409-
<para>
410-
A likely explanation is that another user attempted to start a
411-
<application>postmaster</application>
412-
process on the same port which acquired shared resources and then
413-
died. Since Postgres shared memory keys are based on the port number
414-
assigned to the
415-
<application>postmaster</application>,
416-
such conflicts are likely if there is more than one installation on
417-
a single host. If there are no other
418-
<application>postmaster</application>
419-
processes currently running (see above), run
420-
<application>ipcclean</application>
421-
and try again. If other <application>postmaster</application>
422-
images
423-
are running, you will have to find the owners of those processes to
424-
coordinate the assignment of port numbers and/or removal of unused
425-
shared memory segments.
426-
</para>
427-
</listitem>
428-
</varlistentry>
429403
</variablelist>
430404
</para>
431405
</refsect2>

‎src/backend/access/transam/xlog.c

Lines changed: 1 addition & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -6,7 +6,7 @@
66
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc
77
* Portions Copyright (c) 1994, Regents of the University of California
88
*
9-
* $Header: /cvsroot/pgsql/src/backend/access/transam/xlog.c,v 1.35 2000/11/27 05:36:12 tgl Exp $
9+
* $Header: /cvsroot/pgsql/src/backend/access/transam/xlog.c,v 1.36 2000/11/28 23:27:54 tgl Exp $
1010
*
1111
*-------------------------------------------------------------------------
1212
*/
@@ -85,12 +85,6 @@ typedef struct XLogCtlWrite
8585
}XLogCtlWrite;
8686

8787

88-
#ifndefHAS_TEST_AND_SET
89-
#defineTAS(lck)0
90-
#defineS_UNLOCK(lck)
91-
#defineS_INIT_LOCK(lck)
92-
#endif
93-
9488
typedefstructXLogCtlData
9589
{
9690
XLogCtlInsertInsert;
@@ -102,12 +96,10 @@ typedef struct XLogCtlData
10296
uint32XLogCacheByte;
10397
uint32XLogCacheBlck;
10498
StartUpIDThisStartUpID;
105-
#ifdefHAS_TEST_AND_SET
10699
slock_tinsert_lck;
107100
slock_tinfo_lck;
108101
slock_tlgwr_lck;
109102
slock_tchkp_lck;/* checkpoint lock */
110-
#endif
111103
}XLogCtlData;
112104

113105
staticXLogCtlData*XLogCtl=NULL;

‎src/backend/commands/async.c

Lines changed: 5 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -7,7 +7,7 @@
77
* Portions Copyright (c) 1994, Regents of the University of California
88
*
99
* IDENTIFICATION
10-
* $Header: /cvsroot/pgsql/src/backend/commands/async.c,v 1.72 2000/11/21 21:15:59 petere Exp $
10+
* $Header: /cvsroot/pgsql/src/backend/commands/async.c,v 1.73 2000/11/28 23:27:54 tgl Exp $
1111
*
1212
*-------------------------------------------------------------------------
1313
*/
@@ -119,8 +119,8 @@ static Dllist *pendingNotifies = NULL;
119119
staticvolatileintnotifyInterruptEnabled=0;
120120
staticvolatileintnotifyInterruptOccurred=0;
121121

122-
/* True if we've registered an on_shmem_exit cleanup(or at least tried to).*/
123-
staticintunlistenExitRegistered=0;
122+
/* True if we've registered an on_shmem_exit cleanup */
123+
staticboolunlistenExitRegistered=false;
124124

125125

126126
staticvoidAsync_UnlistenAll(void);
@@ -253,9 +253,8 @@ Async_Listen(char *relname, int pid)
253253
*/
254254
if (!unlistenExitRegistered)
255255
{
256-
if (on_shmem_exit(Async_UnlistenOnExit,0)<0)
257-
elog(NOTICE,"Async_Listen: out of shmem_exit slots");
258-
unlistenExitRegistered=1;
256+
on_shmem_exit(Async_UnlistenOnExit,0);
257+
unlistenExitRegistered= true;
259258
}
260259
}
261260

‎src/backend/postmaster/postmaster.c

Lines changed: 10 additions & 87 deletions
Original file line numberDiff line numberDiff line change
@@ -11,7 +11,7 @@
1111
*
1212
*
1313
* IDENTIFICATION
14-
* $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.193 2000/11/27 04:03:20 inoue Exp $
14+
* $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.194 2000/11/28 23:27:55 tgl Exp $
1515
*
1616
* NOTES
1717
*
@@ -117,26 +117,6 @@ int PostPortNumber;
117117
char*UnixSocketDir;
118118
char*Virtual_host;
119119

120-
/*
121-
* This is a sequence number that indicates how many times we've had to
122-
* throw away the shared memory and start over because we doubted its
123-
* integrity.It starts off at zero and is incremented every time we
124-
* start over. We use this to ensure that we use a new IPC shared memory
125-
* key for the new shared memory segment in case the old segment isn't
126-
* entirely gone yet.
127-
*
128-
* The sequence actually cycles back to 0 after 9, so pathologically there
129-
* could be an IPC failure if 10 sets of backends are all stuck and won't
130-
* release IPC resources.
131-
*/
132-
staticshortshmem_seq=0;
133-
134-
/*
135-
* This is the base IPC shared memory key. Other keys are generated by
136-
* adding to this.
137-
*/
138-
staticIpcMemoryKeyipc_key;
139-
140120
/*
141121
* MaxBackends is the actual limit on the number of backends we will
142122
* start. The default is established by configure, but it can be
@@ -1292,39 +1272,6 @@ ConnFree(Port *conn)
12921272
free(conn);
12931273
}
12941274

1295-
/*
1296-
* get_host_port -- return a pseudo port number (16 bits)
1297-
* derived from the primary IP address of Virtual_host.
1298-
*/
1299-
staticunsigned short
1300-
get_host_port(void)
1301-
{
1302-
staticunsigned shorthostPort=0;
1303-
1304-
if (hostPort==0)
1305-
{
1306-
SockAddrsaddr;
1307-
structhostent*hp;
1308-
1309-
hp=gethostbyname(Virtual_host);
1310-
if ((hp==NULL)|| (hp->h_addrtype!=AF_INET))
1311-
{
1312-
charmsg[1024];
1313-
snprintf(msg,sizeof(msg),
1314-
"FATAL: get_host_port: gethostbyname(%s) failed\n",
1315-
Virtual_host);
1316-
fputs(msg,stderr);
1317-
pqdebug("%s",msg);
1318-
exit(1);
1319-
}
1320-
memmove((char*)&(saddr.in.sin_addr),
1321-
(char*)hp->h_addr,
1322-
hp->h_length);
1323-
hostPort=ntohl(saddr.in.sin_addr.s_addr)&0xFFFF;
1324-
}
1325-
1326-
returnhostPort;
1327-
}
13281275

13291276
/*
13301277
* reset_shared -- reset shared memory and semaphores
@@ -1333,40 +1280,16 @@ static void
13331280
reset_shared(unsigned shortport)
13341281
{
13351282
/*
1336-
* A typical ipc_key is 5432001, which is port 5432, sequence
1337-
* number 0, and 01 as the index in IPCKeyGetBufferMemoryKey().
1338-
* The 32-bit INT_MAX is 2147483 6 47.
1339-
*
1340-
* The default algorithm for calculating the IPC keys assumes that all
1341-
* instances of postmaster on a given host are listening on different
1342-
* ports. In order to work (prevent shared memory collisions) if you
1343-
* run multiple PostgreSQL instances on the same port and different IP
1344-
* addresses on a host, we change the algorithm if you give postmaster
1345-
* the -h option, or set PGHOST, to a value other than the internal
1346-
* default.
1347-
*
1348-
* If Virtual_host is set, then we generate the IPC keys using the
1349-
* last two octets of the IP address instead of the port number.
1350-
* This algorithm assumes that no one will run multiple PostgreSQL
1351-
* instances on one host using two IP addresses that have the same two
1352-
* last octets in different class C networks. If anyone does, it
1353-
* would be rare.
1354-
*
1355-
* So, if you use -h or PGHOST, don't try to run two instances of
1356-
* PostgreSQL on the same IP address but different ports. If you
1357-
* don't use them, then you must use different ports (via -p or
1358-
* PGPORT). And, of course, don't try to use both approaches on one
1359-
* host.
1283+
* Reset assignment of shared mem and semaphore IPC keys.
1284+
* Doing this means that in normal cases we'll assign the same keys
1285+
* on each "cycle of life", and thereby avoid leaving dead IPC objects
1286+
* floating around if the postmaster crashes and is restarted.
13601287
*/
1361-
1362-
if (Virtual_host[0]!='\0')
1363-
port=get_host_port();
1364-
1365-
ipc_key=port*1000+shmem_seq*100;
1366-
CreateSharedMemoryAndSemaphores(ipc_key,MaxBackends);
1367-
shmem_seq+=1;
1368-
if (shmem_seq >=10)
1369-
shmem_seq-=10;
1288+
IpcInitKeyAssignment(port);
1289+
/*
1290+
* Create or re-create shared memory and semaphores.
1291+
*/
1292+
CreateSharedMemoryAndSemaphores(false,MaxBackends);
13701293
}
13711294

13721295

‎src/backend/storage/buffer/buf_init.c

Lines changed: 3 additions & 40 deletions
Original file line numberDiff line numberDiff line change
@@ -8,7 +8,7 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.37 2000/10/23 04:10:06 vadim Exp $
11+
* $Header: /cvsroot/pgsql/src/backend/storage/buffer/buf_init.c,v 1.38 2000/11/28 23:27:55 tgl Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
@@ -56,13 +56,6 @@ intNum_Descriptors;
5656
BufferDesc*BufferDescriptors;
5757
BufferBlockBufferBlocks;
5858

59-
#ifndefHAS_TEST_AND_SET
60-
long*NWaitIOBackendP;
61-
62-
#endif
63-
64-
externIpcSemaphoreIdWaitIOSemId;
65-
6659
long*PrivateRefCount;/* also used in freelist.c */
6760
bits8*BufferLocks;/* flag bits showing locks I have set */
6861
BufferTag*BufferTagLastDirtied;/* tag buffer had when last
@@ -139,7 +132,7 @@ long intLocalBufferFlushCount;
139132
* amount of available memory.
140133
*/
141134
void
142-
InitBufferPool(IPCKeykey)
135+
InitBufferPool(void)
143136
{
144137
boolfoundBufs,
145138
foundDescs;
@@ -170,18 +163,6 @@ InitBufferPool(IPCKey key)
170163
ShmemInitStruct("Buffer Blocks",
171164
NBuffers*BLCKSZ,&foundBufs);
172165

173-
#ifndefHAS_TEST_AND_SET
174-
{
175-
boolfoundNWaitIO;
176-
177-
NWaitIOBackendP= (long*)ShmemInitStruct("#Backends Waiting IO",
178-
sizeof(long),
179-
&foundNWaitIO);
180-
if (!foundNWaitIO)
181-
*NWaitIOBackendP=0;
182-
}
183-
#endif
184-
185166
if (foundDescs||foundBufs)
186167
{
187168

@@ -214,10 +195,8 @@ InitBufferPool(IPCKey key)
214195
buf->flags= (BM_DELETED |BM_FREE |BM_VALID);
215196
buf->refcount=0;
216197
buf->buf_id=i;
217-
#ifdefHAS_TEST_AND_SET
218198
S_INIT_LOCK(&(buf->io_in_progress_lock));
219199
S_INIT_LOCK(&(buf->cntx_lock));
220-
#endif
221200
}
222201

223202
/* close the circular queue */
@@ -231,22 +210,6 @@ InitBufferPool(IPCKey key)
231210

232211
SpinRelease(BufMgrLock);
233212

234-
#ifndefHAS_TEST_AND_SET
235-
{
236-
externIpcSemaphoreIdWaitIOSemId;
237-
externIpcSemaphoreIdWaitCLSemId;
238-
239-
WaitIOSemId=IpcSemaphoreCreate(IPCKeyGetWaitIOSemaphoreKey(key),
240-
1,IPCProtection,0,1);
241-
if (WaitIOSemId<0)
242-
elog(FATAL,"InitBufferPool: IpcSemaphoreCreate(WaitIOSemId) failed");
243-
WaitCLSemId=IpcSemaphoreCreate(IPCKeyGetWaitCLSemaphoreKey(key),
244-
1,IPCProtection,
245-
IpcSemaphoreDefaultStartValue,1);
246-
if (WaitCLSemId<0)
247-
elog(FATAL,"InitBufferPool: IpcSemaphoreCreate(WaitCLSemId) failed");
248-
}
249-
#endif
250213
PrivateRefCount= (long*)calloc(NBuffers,sizeof(long));
251214
BufferLocks= (bits8*)calloc(NBuffers,sizeof(bits8));
252215
BufferTagLastDirtied= (BufferTag*)calloc(NBuffers,sizeof(BufferTag));
@@ -262,7 +225,7 @@ InitBufferPool(IPCKey key)
262225
* ----------------------------------------------------
263226
*/
264227
int
265-
BufferShmemSize()
228+
BufferShmemSize(void)
266229
{
267230
intsize=0;
268231

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp