1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
<!--$Id: env_set_tas_spins.html,v 1.1.1.1 2003/11/20 22:14:26 toshok Exp $-->
<!--Copyright 1997-2002 by Sleepycat Software, Inc.-->
<!--All rights reserved.-->
<!--See the file LICENSE for redistribution information.-->
<html>
<head>
<title>Berkeley DB: DB_ENV->set_tas_spins</title>
<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit.">
<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++">
</head>
<body bgcolor=white>
<a name="2"><!--meow--></a>
<table width="100%"><tr valign=top>
<td>
<h1>DB_ENV->set_tas_spins</h1>
</td>
<td align=right>
<a href="../api_c/c_index.html"><img src="../images/api.gif" alt="API"></a><a href="../reftoc.html"><img src="../images/ref.gif" alt="Ref"></a>
</td></tr></table>
<hr size=1 noshade>
<tt>
<h3><pre>
#include <db.h>
<p>
int
DB_ENV->set_tas_spins(DB_ENV *dbenv, u_int32_t tas_spins);
</pre></h3>
<h1>Description</h1>
<p>Specify that test-and-set mutexes should spin <b>tas_spins</b> times
without blocking. The value defaults to 1 on uniprocessor systems and
to 50 times the number of processors on multiprocessor systems.
<p>The DB_ENV->set_tas_spins method configures operations performed using the specified
<a href="../api_c/env_class.html">DB_ENV</a> handle, not all operations performed on the underlying
database environment.
<p>The DB_ENV->set_tas_spins interface may be called at any time during the life of
the application.
<p>The DB_ENV->set_tas_spins method returns a non-zero error value on failure and 0 on success.
<p>The database environment's test-and-set spin count may also be set using the environment's
<b>DB_CONFIG</b> file. The syntax of the entry in that file is a
single line with the string "set_tas_spins", one or more whitespace characters,
and the number of spins. Because the <b>DB_CONFIG</b> file is read when the database
environment is opened, it will silently overrule configuration done
before that time.
<h1>Errors</h1>
<p>The DB_ENV->set_tas_spins method may fail and return a non-zero error for the following conditions:
<p><dl compact>
<p><dt>EINVAL<dd>An invalid flag value or parameter was specified.
</dl>
<p>The DB_ENV->set_tas_spins method may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions.
If a catastrophic error has occurred, the DB_ENV->set_tas_spins method may fail and
return <a href="../ref/program/errorret.html#DB_RUNRECOVERY">DB_RUNRECOVERY</a>,
in which case all subsequent Berkeley DB calls will fail in the same way.
<h1>Class</h1>
<a href="../api_c/env_class.html">DB_ENV</a>
<h1>See Also</h1>
<a href="../api_c/env_list.html">Database Environments and Related Methods</a>
</tt>
<table width="100%"><tr><td><br></td><td align=right>
<a href="../api_c/c_index.html"><img src="../images/api.gif" alt="API"></a><a href="../reftoc.html"><img src="../images/ref.gif" alt="Ref"></a>
</td></tr></table>
<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font>
</body>
</html>
|
