blob: 2befb58870a492ec757727332267297be1061951 (
plain) (
blame)
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
64
65
|
#pragma once
#include <base/scope_guard.h>
#include <Common/LockMemoryExceptionInThread.h>
/// Same as SCOPE_EXIT() but block the MEMORY_LIMIT_EXCEEDED errors.
///
/// Typical example of SCOPE_EXIT_MEMORY() usage is when code under it may do
/// some tiny allocations, that may fail under high memory pressure or/and low
/// max_memory_usage (and related limits).
///
/// NOTE: it should be used with caution.
#define SCOPE_EXIT_MEMORY(...) SCOPE_EXIT( \
LockMemoryExceptionInThread lock_memory_tracker(VariableContext::Global); \
__VA_ARGS__; \
)
/// Same as SCOPE_EXIT() but try/catch/tryLogCurrentException any exceptions.
///
/// SCOPE_EXIT_SAFE() should be used in case the exception during the code
/// under SCOPE_EXIT() is not "that fatal" and error message in log is enough.
///
/// Good example is calling CurrentThread::detachQueryIfNotDetached().
///
/// Anti-pattern is calling WriteBuffer::finalize() under SCOPE_EXIT_SAFE()
/// (since finalize() can do final write and it is better to fail abnormally
/// instead of ignoring write error).
///
/// NOTE: it should be used with double caution.
#define SCOPE_EXIT_SAFE(...) SCOPE_EXIT( \
try \
{ \
__VA_ARGS__; \
} \
catch (...) \
{ \
DB::tryLogCurrentException(__PRETTY_FUNCTION__); \
} \
)
/// Same as SCOPE_EXIT() but:
/// - block the MEMORY_LIMIT_EXCEEDED errors,
/// - try/catch/tryLogCurrentException any exceptions.
///
/// SCOPE_EXIT_MEMORY_SAFE() can be used when the error can be ignored, and in
/// addition to SCOPE_EXIT_SAFE() it will also lock MEMORY_LIMIT_EXCEEDED to
/// avoid such exceptions.
///
/// It does exists as a separate helper, since you do not need to lock
/// MEMORY_LIMIT_EXCEEDED always (there are cases when code under SCOPE_EXIT does
/// not do any allocations, while LockExceptionInThread increment atomic
/// variable).
///
/// NOTE: it should be used with triple caution.
#define SCOPE_EXIT_MEMORY_SAFE(...) SCOPE_EXIT( \
try \
{ \
LockMemoryExceptionInThread lock_memory_tracker(VariableContext::Global); \
__VA_ARGS__; \
} \
catch (...) \
{ \
DB::tryLogCurrentException(__PRETTY_FUNCTION__); \
} \
)
|
