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shm cleanups

PATCH New Christoph Rohland 1 participant 1 message Nov 3, 1999

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PATCH 1/1 shm cleanups

Hi Linus,

Here is a patch against 2.3.25 which

1) avoids vmalloc in the shm coding.
2) cleans a lot of cruft out of the shm headers
3) makes shm sysctl'able

I did test it a lot on SMP/HIGHMEM. Since 2.3.25 with and without this breaks on swapping shm and other high memory load conditions I could not verify everything. But I would like to see this in the mainstream kernel. I will then proceed debugging the swapping issues.

Greetings
Christoph

--Multipart_Wed_Nov__3_20:17:09_1999-1
Content-Type: application/octet-stream
Content-Disposition: attachment; filename="patch-25-shm3"
Content-Transfer-Encoding: 7bit

arch/i386/kernel/sys_i386.c +64 -79
diff -uNr 2.3.25/arch/i386/kernel/sys_i386.c 2.3.25-shm3/arch/i386/kernel/sys_i386.c
@@ -116,86 +116,71 @@
 	version = call >> 16; /* hack for backward compatibility */
 	call &= 0xffff;
 
-	if (call <= SEMCTL)
-		switch (call) {
-		case SEMOP:
-			return sys_semop (first, (struct sembuf *)ptr, second);
-		case SEMGET:
-			return sys_semget (first, second, third);
-		case SEMCTL: {
-			union semun fourth;
-			if (!ptr)
-				return -EINVAL;
-			if (get_user(fourth.__pad, (void **) ptr))
-				return -EFAULT;
-			return sys_semctl (first, second, third, fourth);
-			}
-		default:
-			return -EINVAL;
-		}
+        switch (call) {
+        case SEMOP:
+                return sys_semop (first, (struct sembuf *)ptr, second);
+        case SEMGET:
+                return sys_semget (first, second, third);
+        case SEMCTL: {
+                union semun fourth;
+                if (!ptr)
+                        return -EINVAL;
+                if (get_user(fourth.__pad, (void **) ptr))
+                        return -EFAULT;
+                return sys_semctl (first, second, third, fourth);
+        }
 
-	if (call <= MSGCTL) 
-		switch (call) {
-		case MSGSND:
-			return sys_msgsnd (first, (struct msgbuf *) ptr, 
-					  second, third);
-		case MSGRCV:
-			switch (version) {
-			case 0: {
-				struct ipc_kludge tmp;
-				if (!ptr)
-					return -EINVAL;
-				
-				if (copy_from_user(&tmp,
-						   (struct ipc_kludge *) ptr, 
-						   sizeof (tmp)))
-					return -EFAULT;
-				return sys_msgrcv (first, tmp.msgp, second,
-						   tmp.msgtyp, third);
-				}
-			default:
-				return sys_msgrcv (first,
-						   (struct msgbuf *) ptr,
-						   second, fifth, third);
-			}
-		case MSGGET:
-			return sys_msgget ((key_t) first, second);
-		case MSGCTL:
-			return sys_msgctl (first, second,
-					   (struct msqid_ds *) ptr);
-		default:
-			return -EINVAL;
-		}
-	if (call <= SHMCTL) 
-		switch (call) {
-		case SHMAT:
-			switch (version) {
-			default: {
-				ulong raddr;
-				ret = sys_shmat (first, (char *) ptr,
-						 second, &raddr);
-				if (ret)
-					return ret;
-				return put_user (raddr, (ulong *) third);
-			}
-			case 1:	/* iBCS2 emulator entry point */
-				if (!segment_eq(get_fs(), get_ds()))
-					return -EINVAL;
-				return sys_shmat (first, (char *) ptr,
-						  second, (ulong *) third);
-			}
-		case SHMDT: 
-			return sys_shmdt ((char *)ptr);
-		case SHMGET:
-			return sys_shmget (first, second, third);
-		case SHMCTL:
-			return sys_shmctl (first, second,
-					   (struct shmid_ds *) ptr);
-		default:
-			return -EINVAL;
-		}
-	
-	return -EINVAL;
+        case MSGSND:
+                return sys_msgsnd (first, (struct msgbuf *) ptr, 
+                                   second, third);
+        case MSGRCV:
+                switch (version) {
+                case 0: {
+                        struct ipc_kludge tmp;
+                        if (!ptr)
+                                return -EINVAL;
+                        
+                        if (copy_from_user(&tmp,
+                                           (struct ipc_kludge *) ptr, 
+                                           sizeof (tmp)))
+                                return -EFAULT;
+                        return sys_msgrcv (first, tmp.msgp, second,
+                                           tmp.msgtyp, third);
+                }
+                default:
+                        return sys_msgrcv (first,
+                                           (struct msgbuf *) ptr,
+                                           second, fifth, third);
+                }
+        case MSGGET:
+                return sys_msgget ((key_t) first, second);
+        case MSGCTL:
+                return sys_msgctl (first, second, (struct msqid_ds *) ptr);
+
+        case SHMAT:
+                switch (version) {
+                default: {
+                        ulong raddr;
+                        ret = sys_shmat (first, (char *) ptr, second, &raddr);
+                        if (ret)
+                                return ret;
+                        return put_user (raddr, (ulong *) third);
+                }
+                case 1:	/* iBCS2 emulator entry point */
+                        if (!segment_eq(get_fs(), get_ds()))
+                                return -EINVAL;
+                        return sys_shmat (first, (char *) ptr, second, (ulong *) third);
+                }
+        case SHMDT: 
+                return sys_shmdt ((char *)ptr);
+        case SHMGET:
+                return sys_shmget (first, second, third);
+        case SHMCTL:
+                return sys_shmctl (first, second,
+                                   (struct shmid_ds *) ptr);
+        default:
+                return -EINVAL;
+        }
 }
 
 /*
include/asm-alpha/shmparam.h +1 -42

48 lines not on this page · raw message

include/asm-arm/proc-armo/shmparam.h +1 -3
diff -uNr 2.3.25/include/asm-arm/proc-armo/shmparam.h 2.3.25-shm3/include/asm-arm/proc-armo/shmparam.h
@@ -9,9 +9,7 @@
 #ifndef __ASM_PROC_SHMPARAM_H
 #define __ASM_PROC_SHMPARAM_H
 
-#ifndef SHM_RANGE_START
-#define SHM_RANGE_START	0x00a00000
-#define SHM_RANGE_END	0x00c00000
+#ifndef SHMMAX
 #define SHMMAX		0x003fa000
 #endif
 
include/asm-arm/proc-armv/shmparam.h +1 -3
diff -uNr 2.3.25/include/asm-arm/proc-armv/shmparam.h 2.3.25-shm3/include/asm-arm/proc-armv/shmparam.h
@@ -10,9 +10,7 @@
 #ifndef __ASM_PROC_SHMPARAM_H
 #define __ASM_PROC_SHMPARAM_H
 
-#ifndef SHM_RANGE_START
-#define SHM_RANGE_START	0x50000000
-#define SHM_RANGE_END	0x60000000
+#ifndef SHMMAX
 #define SHMMAX		0x01000000
 #endif
 
include/asm-arm/shmparam.h +1 -34
diff -uNr 2.3.25/include/asm-arm/shmparam.h 2.3.25-shm3/include/asm-arm/shmparam.h
@@ -3,39 +3,6 @@
 
 #include <asm/proc/shmparam.h>
 
-/*
- * Format of a swap-entry for shared memory pages currently out in
- * swap space (see also mm/swap.c).
- *
- * SWP_TYPE = SHM_SWP_TYPE
- * SWP_OFFSET is used as follows:
- *
- *  bits 0..6 : id of shared memory segment page belongs to (SHM_ID)
- *  bits 7..21: index of page within shared memory segment (SHM_IDX)
- *		(actually fewer bits get used since SHMMAX is so low)
- */
-
-/*
- * Keep _SHM_ID_BITS as low as possible since SHMMNI depends on it and
- * there is a static array of size SHMMNI.
- */
-#define _SHM_ID_BITS	7
-#define SHM_ID_MASK	((1<<_SHM_ID_BITS)-1)
-
-#define SHM_IDX_SHIFT	(_SHM_ID_BITS)
-#define _SHM_IDX_BITS	15
-#define SHM_IDX_MASK	((1<<_SHM_IDX_BITS)-1)
-
-/*
- * _SHM_ID_BITS + _SHM_IDX_BITS must be <= 24 on the i386 and
- * SHMMAX <= (PAGE_SIZE << _SHM_IDX_BITS).
- */
-
-#define SHMMIN 1 /* really PAGE_SIZE */	/* min shared seg size (bytes) */
-#define SHMMNI (1<<_SHM_ID_BITS)	/* max num of segs system wide */
-#define SHMALL				/* max shm system wide (pages) */ \
-	(1<<(_SHM_IDX_BITS+_SHM_ID_BITS))
-#define	SHMLBA PAGE_SIZE		/* attach addr a multiple of this */
-#define SHMSEG SHMMNI			/* max shared segs per process */
+#define	SHMLBA PAGE_SIZE		 /* attach addr a multiple of this */
 
 #endif /* _ASMARM_SHMPARAM_H */
include/asm-i386/shmparam.h +1 -41

47 lines not on this page · raw message

include/asm-m68k/shmparam.h +1 -44

50 lines not on this page · raw message

include/asm-mips/shmparam.h +0 -40
diff -uNr 2.3.25/include/asm-mips/shmparam.h 2.3.25-shm3/include/asm-mips/shmparam.h
@@ -1,49 +1,9 @@
 #ifndef __ASM_MIPS_SHMPARAM_H
 #define __ASM_MIPS_SHMPARAM_H
 
-/* address range for shared memory attaches if no address passed to shmat() */
-#define SHM_RANGE_START	0x50000000
-#define SHM_RANGE_END	0x60000000
-
-/*
- * Format of a swap-entry for shared memory pages currently out in
- * swap space (see also mm/swap.c).
- *
- * SWP_TYPE = SHM_SWP_TYPE
- * SWP_OFFSET is used as follows:
- *
- *  bits 0..6 : id of shared memory segment page belongs to (SHM_ID)
- *  bits 7..21: index of page within shared memory segment (SHM_IDX)
- *		(actually fewer bits get used since SHMMAX is so low)
- */
-
-/*
- * Keep _SHM_ID_BITS as low as possible since SHMMNI depends on it and
- * there is a static array of size SHMMNI.
- */
-#define _SHM_ID_BITS	7
-#define SHM_ID_MASK	((1<<_SHM_ID_BITS)-1)
-
-#define SHM_IDX_SHIFT	(_SHM_ID_BITS)
-#define _SHM_IDX_BITS	15
-#define SHM_IDX_MASK	((1<<_SHM_IDX_BITS)-1)
-
-/*
- * _SHM_ID_BITS + _SHM_IDX_BITS must be <= 24 on the i386 and
- * SHMMAX <= (PAGE_SIZE << _SHM_IDX_BITS).
- */
-
-#define SHMMAX 0x2000000		/* max shared seg size (bytes) */
-/* Try not to change the default shipped SHMMAX - people rely on it */
-
-#define SHMMIN 1 /* really PAGE_SIZE */	/* min shared seg size (bytes) */
-#define SHMMNI (1<<_SHM_ID_BITS)	/* max num of segs system wide */
-#define SHMALL				/* max shm system wide (pages) */ \
-	(1<<(_SHM_IDX_BITS+_SHM_ID_BITS))
 /*
  * This constant is very large but the ABI in it's wisdom says ...
  */
 #define	SHMLBA 0x40000			/* attach addr a multiple of this */
-#define SHMSEG SHMMNI			/* max shared segs per process */
 
 #endif /* __ASM_MIPS_SHMPARAM_H */
include/asm-ppc/shmparam.h +1 -39
diff -uNr 2.3.25/include/asm-ppc/shmparam.h 2.3.25-shm3/include/asm-ppc/shmparam.h
@@ -1,44 +1,6 @@
 #ifndef _PPC_SHMPARAM_H
 #define _PPC_SHMPARAM_H
 
-/* address range for shared memory attaches if no address passed to shmat() */
-#define SHM_RANGE_START	0x50000000
-#define SHM_RANGE_END	0x60000000
-
-/*
- * Format of a swap-entry for shared memory pages currently out in
- * swap space (see also mm/swap.c).
- *
- * SWP_TYPE = SHM_SWP_TYPE
- * SWP_OFFSET is used as follows:
- *
- *  bits 0..6 : id of shared memory segment page belongs to (SHM_ID)
- *  bits 7..21: index of page within shared memory segment (SHM_IDX)
- *		(actually fewer bits get used since SHMMAX is so low)
- */
-
-/*
- * Keep _SHM_ID_BITS as low as possible since SHMMNI depends on it and
- * there is a static array of size SHMMNI.
- */
-#define _SHM_ID_BITS	7
-#define SHM_ID_MASK	((1<<_SHM_ID_BITS)-1)
-
-#define SHM_IDX_SHIFT	(_SHM_ID_BITS)
-#define _SHM_IDX_BITS	15
-#define SHM_IDX_MASK	((1<<_SHM_IDX_BITS)-1)
-
-/*
- * _SHM_ID_BITS + _SHM_IDX_BITS must be <= 24 on the i386 and
- * SHMMAX <= (PAGE_SIZE << _SHM_IDX_BITS).
- */
-
-#define SHMMAX 0x2000000		/* max shared seg size (bytes) */
-#define SHMMIN 1 /* really PAGE_SIZE */	/* min shared seg size (bytes) */
-#define SHMMNI (1<<_SHM_ID_BITS)	/* max num of segs system wide */
-#define SHMALL				/* max shm system wide (pages) */ \
-	(1<<(_SHM_IDX_BITS+_SHM_ID_BITS))
-#define	SHMLBA PAGE_SIZE		/* attach addr a multiple of this */
-#define SHMSEG SHMMNI			/* max shared segs per process */
+#define	SHMLBA PAGE_SIZE		 /* attach addr a multiple of this */
 
 #endif /* _PPC_SHMPARAM_H */
include/asm-sh/shmparam.h +1 -41

47 lines not on this page · raw message

include/asm-sparc/shmparam.h +1 -39
diff -uNr 2.3.25/include/asm-sparc/shmparam.h 2.3.25-shm3/include/asm-sparc/shmparam.h
@@ -2,44 +2,6 @@
 #ifndef _ASMSPARC_SHMPARAM_H
 #define _ASMSPARC_SHMPARAM_H
 
-/* address range for shared memory attaches if no address passed to shmat() */
-#define SHM_RANGE_START	0x10000000
-#define SHM_RANGE_END	0x20000000
-
-/*
- * Format of a swap-entry for shared memory pages currently out in
- * swap space (see also mm/swap.c).
- *
- * SWP_TYPE = SHM_SWP_TYPE
- * SWP_OFFSET is used as follows:
- *
- *  bits 0..6 : id of shared memory segment page belongs to (SHM_ID)
- *  bits 7..21: index of page within shared memory segment (SHM_IDX)
- *		(actually fewer bits get used since SHMMAX is so low)
- */
-
-/*
- * Keep _SHM_ID_BITS as low as possible since SHMMNI depends on it and
- * there is a static array of size SHMMNI.
- */
-#define _SHM_ID_BITS	7
-#define SHM_ID_MASK	((1<<_SHM_ID_BITS)-1)
-
-#define SHM_IDX_SHIFT	(_SHM_ID_BITS)
-#define _SHM_IDX_BITS	15
-#define SHM_IDX_MASK	((1<<_SHM_IDX_BITS)-1)
-
-/*
- * _SHM_ID_BITS + _SHM_IDX_BITS must be <= 24 on the i386 and
- * SHMMAX <= (PAGE_SIZE << _SHM_IDX_BITS).
- */
-
-#define SHMMAX 0x1000000		/* max shared seg size (bytes) */
-#define SHMMIN 1 /* really PAGE_SIZE */	/* min shared seg size (bytes) */
-#define SHMMNI (1<<_SHM_ID_BITS)	/* max num of segs system wide */
-#define SHMALL				/* max shm system wide (pages) */ \
-	(1<<(_SHM_IDX_BITS+_SHM_ID_BITS))
-#define	SHMLBA PAGE_SIZE		/* attach addr a multiple of this */
-#define SHMSEG SHMMNI			/* max shared segs per process */
+#define	SHMLBA PAGE_SIZE		 /* attach addr a multiple of this */
 
 #endif /* _ASMSPARC_SHMPARAM_H */
include/asm-sparc64/shmparam.h +0 -40
diff -uNr 2.3.25/include/asm-sparc64/shmparam.h 2.3.25-shm3/include/asm-sparc64/shmparam.h
@@ -2,46 +2,6 @@
 #ifndef _ASMSPARC64_SHMPARAM_H
 #define _ASMSPARC64_SHMPARAM_H
 
-/* XXX Redo most of this... */
-
-/* address range for shared memory attaches if no address passed to shmat() */
-#define SHM_RANGE_START	0x10000000
-#define SHM_RANGE_END	0x20000000
-
-/*
- * Format of a swap-entry for shared memory pages currently out in
- * swap space (see also mm/swap.c).
- *
- * SWP_TYPE = SHM_SWP_TYPE
- * SWP_OFFSET is used as follows:
- *
- *  bits 0..6 : id of shared memory segment page belongs to (SHM_ID)
- *  bits 7..21: index of page within shared memory segment (SHM_IDX)
- *		(actually fewer bits get used since SHMMAX is so low)
- */
-
-/*
- * Keep _SHM_ID_BITS as low as possible since SHMMNI depends on it and
- * there is a static array of size SHMMNI.
- */
-#define _SHM_ID_BITS	7
-#define SHM_ID_MASK	((1<<_SHM_ID_BITS)-1)
-
-#define SHM_IDX_SHIFT	(_SHM_ID_BITS)
-#define _SHM_IDX_BITS	15
-#define SHM_IDX_MASK	((1<<_SHM_IDX_BITS)-1)
-
-/*
- * _SHM_ID_BITS + _SHM_IDX_BITS must be <= 24 on the i386 and
- * SHMMAX <= (PAGE_SIZE << _SHM_IDX_BITS).
- */
-
-#define SHMMAX 0x1000000		/* max shared seg size (bytes) */
-#define SHMMIN 1 /* really PAGE_SIZE */	/* min shared seg size (bytes) */
-#define SHMMNI (1<<_SHM_ID_BITS)	/* max num of segs system wide */
-#define SHMALL				/* max shm system wide (pages) */ \
-	(1<<(_SHM_IDX_BITS+_SHM_ID_BITS))
 #define	SHMLBA (PAGE_SIZE<<1)		/* attach addr a multiple of this */
-#define SHMSEG SHMMNI			/* max shared segs per process */
 
 #endif /* _ASMSPARC64_SHMPARAM_H */
include/linux/shm.h +11 -9
diff -uNr 2.3.25/include/linux/shm.h 2.3.25-shm3/include/linux/shm.h
@@ -3,6 +3,17 @@
 
 #include <linux/ipc.h>
 
+/*
+ * SHMMAX, SHMMNI and SHMALL are upper limits are defaults which can
+ * be increased by sysctl
+ */
+
+#define SHMMAX 0x2000000		 /* max shared seg size (bytes) */
+#define SHMMIN 1 /* really PAGE_SIZE */	 /* min shared seg size (bytes) */
+#define SHMMNI 128			 /* max num of segs system wide */
+#define SHMALL (SHMMAX/PAGE_SIZE*SHMMNI) /* max shm system wide (pages) */
+#define SHMSEG SHMMNI			 /* max shared segs per process */
+
 #include <asm/shmparam.h>
 
 struct shmid_ds {
@@ -17,15 +28,6 @@
 	unsigned short 		shm_unused;	/* compatibility */
 	void 			*shm_unused2;	/* ditto - used by DIPC */
 	void			*shm_unused3;	/* unused */
-};
-
-struct shmid_kernel
-{	
-	struct shmid_ds		u;
-	/* the following are private */
-	unsigned long		shm_npages;	/* size of segment (pages) */
-	pte_t			*shm_pages;	/* array of ptrs to frames -> SHMMAX */ 
-	struct vm_area_struct	*attaches;	/* descriptors for attaches */
 };
 
 /* permission flag for shmget */
include/linux/swap.h +0 -11
diff -uNr 2.3.25/include/linux/swap.h 2.3.25-shm3/include/linux/swap.h
@@ -122,17 +122,6 @@
 asmlinkage long sys_swapoff(const char *);
 asmlinkage long sys_swapon(const char *, int);
 
-/*
- * vm_ops not present page codes for shared memory.
- *
- * Will go away eventually..
- */
-#define SHM_SWP_TYPE 0x20
-
-/*
- * swap cache stuff (in linux/mm/swap_state.c)
- */
-
 #define SWAP_CACHE_INFO
 
 #ifdef SWAP_CACHE_INFO
include/linux/sysctl.h +1 -2
diff -uNr 2.3.25/include/linux/sysctl.h 2.3.25-shm3/include/linux/sysctl.h
@@ -103,8 +103,7 @@
 	KERN_MSGPOOL=37,        /* int: Maximum system message pool size */
 	KERN_SYSRQ=38,		/* int: Sysreq enable */
 	KERN_MAX_THREADS=39,    /* int: Maximum nr of threads in the system */
- 	KERN_RANDOM=40,		/* Random driver */
- 	KERN_SHMALL=41		/* int: Maximum size of shared memory */
+ 	KERN_RANDOM=40		/* Random driver */
 };
 
 
ipc/shm.c +189 -75

537 lines not on this page · raw message

ipc/util.c +2 -0
diff -uNr 2.3.25/ipc/util.c 2.3.25-shm3/ipc/util.c
@@ -14,6 +14,8 @@
 #include <linux/init.h>
 #include <linux/msg.h>
 
+#include "util.h"
+
 #if defined(CONFIG_SYSVIPC)
 
 extern void sem_init (void), msg_init (void), shm_init (void);
ipc/util.h +12 -0
diff -uNr 2.3.25/ipc/util.h 2.3.25-shm3/ipc/util.h
@@ -0,0 +1,12 @@
+/*
+ * linux/ipc/util.h
+ * Copyright (C) 1999 Christoph Rohland
+ */
+
+/*
+ * IPCMNI is the absolute maximum for ipc identifier. This is used to
+ * detect stale identifiers
+ */
+#define IPCMNI (1<<15)          
+
+extern int ipcperms (struct ipc_perm *ipcp, short shmflg);
kernel/sysctl.c +2 -2
diff -uNr 2.3.25/kernel/sysctl.c 2.3.25-shm3/kernel/sysctl.c
@@ -49,7 +49,7 @@
 extern int sg_big_buff;
 #endif
 #ifdef CONFIG_SYSVIPC
-extern size_t shmmax;
+extern size_t shm_prm[];
 #endif
 
 #ifdef __sparc__
@@ -213,7 +213,7 @@
 	{KERN_RTSIGMAX, "rtsig-max", &max_queued_signals, sizeof(int),
 	 0644, NULL, &proc_dointvec},
 #ifdef CONFIG_SYSVIPC
-	{KERN_SHMMAX, "shmmax", &shmmax, sizeof (size_t),
+	{KERN_SHMMAX, "shmmax", &shm_prm, 3*sizeof (size_t),
 	 0644, NULL, &proc_doulongvec_minmax},
 #endif
 #ifdef CONFIG_MAGIC_SYSRQ
mm/swap_state.c +0 -4
diff -uNr 2.3.25/mm/swap_state.c 2.3.25-shm3/mm/swap_state.c
@@ -68,8 +68,6 @@
 	if (!entry.val)
 		goto out;
 	type = SWP_TYPE(entry);
-	if (type & SHM_SWP_TYPE)
-		goto out;
 	if (type >= nr_swapfiles)
 		goto bad_file;
 	p = type + swap_info;
@@ -115,8 +113,6 @@
 	if (!entry.val)
 		goto bad_entry;
 	type = SWP_TYPE(entry);
-	if (type & SHM_SWP_TYPE)
-		goto out;
 	if (type >= nr_swapfiles)
 		goto bad_file;
 	p = type + swap_info;
mm/swapfile.c +0 -4
diff -uNr 2.3.25/mm/swapfile.c 2.3.25-shm3/mm/swapfile.c
@@ -135,8 +135,6 @@
 		goto out;
 
 	type = SWP_TYPE(entry);
-	if (type & SHM_SWP_TYPE)
-		goto out;
 	if (type >= nr_swapfiles)
 		goto bad_nofile;
 	p = & swap_info[type];
@@ -190,8 +188,6 @@
 		goto new_swap_entry;
 	entry.val = page->index;
 	type = SWP_TYPE(entry);
-	if (type & SHM_SWP_TYPE)
-		goto new_swap_entry;
 	if (type >= nr_swapfiles)
 		goto new_swap_entry;
 	p = type + swap_info;

--Multipart_Wed_Nov__3_20:17:09_1999-1--
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