xrootd
XrdBuffer.hh
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1 #ifndef __XrdBuffer_H__
2 #define __XrdBuffer_H__
3 /******************************************************************************/
4 /* */
5 /* X r d B u f f e r . h h */
6 /* */
7 /* (c) 2004 by the Board of Trustees of the Leland Stanford, Jr., University */
8 /* Produced by Andrew Hanushevsky for Stanford University under contract */
9 /* DE-AC02-76-SFO0515 with the Department of Energy */
10 /* */
11 /* This file is part of the XRootD software suite. */
12 /* */
13 /* XRootD is free software: you can redistribute it and/or modify it under */
14 /* the terms of the GNU Lesser General Public License as published by the */
15 /* Free Software Foundation, either version 3 of the License, or (at your */
16 /* option) any later version. */
17 /* */
18 /* XRootD is distributed in the hope that it will be useful, but WITHOUT */
19 /* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or */
20 /* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public */
21 /* License for more details. */
22 /* */
23 /* You should have received a copy of the GNU Lesser General Public License */
24 /* along with XRootD in a file called COPYING.LESSER (LGPL license) and file */
25 /* COPYING (GPL license). If not, see <http://www.gnu.org/licenses/>. */
26 /* */
27 /* The copyright holder's institutional names and contributor's names may not */
28 /* be used to endorse or promote products derived from this software without */
29 /* specific prior written permission of the institution or contributor. */
30 /******************************************************************************/
31 
32 #include <stdlib.h>
33 #include <unistd.h>
34 #include <sys/types.h>
35 #include "XrdSys/XrdSysPthread.hh"
36 
37 /******************************************************************************/
38 /* x r d _ B u f f e r */
39 /******************************************************************************/
40 
41 class XrdBuffer
42 {
43 public:
44 
45 char * buff; // -> buffer
46 int bsize; // size of this buffer
47 
48  XrdBuffer(char *bp, int sz, int ix)
49  {buff = bp; bsize = sz; bindex = ix; next = 0;}
50 
51  ~XrdBuffer() {if (buff) free(buff);}
52 
53  friend class XrdBuffManager;
54 private:
55 
57  int bindex;
58 static int pagesz;
59 };
60 
61 /******************************************************************************/
62 /* x r d _ B u f f M a n a g e r */
63 /******************************************************************************/
64 
65 #define XRD_BUCKETS 12
66 #define XRD_BUSHIFT 10
67 
68 // There should be only one instance of this class per buffer pool.
69 //
70 class XrdOucTrace;
71 class XrdSysError;
72 
74 {
75 public:
76 
77 void Init();
78 
79 XrdBuffer *Obtain(int bsz);
80 
81 int Recalc(int bsz);
82 
83 void Release(XrdBuffer *bp);
84 
85 int MaxSize() {return maxsz;}
86 
87 void Reshape();
88 
89 void Set(int maxmem=-1, int minw=-1);
90 
91 int Stats(char *buff, int blen, int do_sync=0);
92 
93  XrdBuffManager(XrdSysError *lP, XrdOucTrace *tP, int minrst=20*60);
94 
95  ~XrdBuffManager() {} // The buffmanager is never deleted
96 
97 private:
98 
101 
102 const int slots;
103 const int shift;
104 const int pagsz;
105 const int maxsz;
106 
107 struct {XrdBuffer *bnext;
108  int numbuf;
109  int numreq;
110  } bucket[XRD_BUCKETS]; // 1K to 1<<(szshift+slots-1)M buffers
111 
112 int totreq;
113 int totbuf;
114 long long totalo;
115 long long maxalo;
116 int minrsw;
118 int totadj;
119 
121 static const char *TraceID;
122 };
123 #endif