Boost Unordered Translation (zh_Hans)/Doc / Modules / Root / Pages / Concurrent (adoc)

Exit Zen

9 :81

	English On the other hand, a visitation function can _not_ access the container itself: 79/10000 · 79
10 :90

	English Access to a different container is allowed, though: 51/10000 · 51
11 :101

	English But, in general, visitation functions should be as lightweight as possible to reduce contention and increase parallelization. In some cases, moving heavy work outside of visitation may be beneficial: 199/10000 · 199
12 :116

	English Visitation is prominent in the API provided by concurrent containers, and many classical operations have visitation-enabled variations: 135/10000 · 135
13 :128

	English Note that in this last example the visitation function could actually _modify_ the element: as a general rule, operations on a concurrent map `m` will grant visitation functions const/non-const access to the element depending on whether `m` is const/non-const. Const access can be always be explicitly requested by using `cvisit` overloads (for instance, `insert_or_cvisit`) and may result in higher parallelization. For concurrent sets, on the other hand, visitation is always const access. 492/10000 · 492
14 :136

	English Although expected to be used much less frequently, concurrent containers also provide insertion operations where an element can be visited right after element creation (in addition to the usual visitation when an equivalent element already exists): 248/10000 · 248
15 :152

	English Consult the references of `xref:reference/concurrent_node_set.adoc#concurrent_node_set[boost::concurrent_node_set]`, `xref:reference/concurrent_node_map.adoc#concurrent_node_map[boost::concurrent_node_map]`, `xref:reference/concurrent_flat_set.adoc#concurrent_flat_set[boost::concurrent_flat_set]` and `xref:reference/concurrent_flat_map.adoc#concurrent_flat_map[boost::concurrent_flat_map]` for the complete list of visitation-enabled operations. 447/10000 · 447
16 :159

	English Whole-Table Visitation 22/10000 · 22
17 :161

	English In the absence of iterators, `visit_all` is provided as an alternative way to process all the elements in the container: 120/10000 · 120
18 :171

	English In C++17 compilers implementing standard parallel algorithms, whole-table visitation can be parallelized: 105/10000 · 105
19 :181

	English Traversal can be interrupted midway: 36/10000 · 36
20 :202

	English There is one last whole-table visitation operation, `erase_if`: 63/10000 · 63
21 :211

	English `visit_while` and `erase_if` can also be parallelized. Note that, in order to increase efficiency, whole-table visitation operations do not block the table during execution: this implies that elements may be inserted, modified or erased by other threads during visitation. It is advisable not to assume too much about the exact global state of a concurrent container at any point in your program. 396/10000 · 396
22 :217

	English Bulk visitation 15/10000 · 15
23 :219

	English Suppose you have an `std::array` of keys you want to look up for in a concurrent map: 85/10000 · 85
24 :230

	English _Bulk visitation_ allows us to pass all the keys in one operation: 66/10000 · 66
25 :237

	English This functionality is not provided for mere syntactic convenience, though: by processing all the keys at once, some internal optimizations can be applied that increase performance over the regular, one-at-a-time case (consult the xref:benchmarks.adoc#benchmarks_boostconcurrent_flatnode_map[benchmarks]). In fact, it may be beneficial to buffer incoming keys so that they can be bulk visited in chunks: 402/10000 · 402
26 :261

	English There's a latency/throughput tradeoff here: it will take longer for incoming keys to be processed (since they are buffered), but the number of processed keys per second is higher. `bulk_visit_size` is the recommended chunk size —smaller buffers may yield worse performance. 273/10000 · 273
27 :266

	English Blocking Operations 19/10000 · 19
28 :268

	English Concurrent containers can be copied, assigned, cleared and merged just like any other Boost.Unordered container. Unlike most other operations, these are _blocking_, that is, all other threads are prevented from accesing the tables involved while a copy, assignment, clear or merge operation is in progress. Blocking is taken care of automatically by the library and the user need not take any special precaution, but overall performance may be affected. 453/10000 · 453

Shortcut	Action
`?`	Open available keyboard shortcuts.
`Alt` + `Home`	Navigate to the first translation in the current search.
`Alt` + `End`	Navigate to the last translation in the current search.
`Alt` + `PageUp` or `Ctrl` + `↑` or `Alt` + `↑` or `Cmd` + `↑` or	Navigate to the previous translation in the current search.
`Alt` + `PageDown` or `Ctrl` + `↓` or `Alt` + `↓` or `Cmd` + `↓` or	Navigate to the next translation in the current search.
`Ctrl` + `Enter` or `Cmd` + `Enter`	Submit current form; this works the same as pressing Save and continue while editing translation.
`Ctrl` + `Shift` + `Enter` or `Cmd` + `Shift` +`Enter`	Unmark translation as Needing edit and submit it.
`Alt` + `Enter` or `Option` + `Enter`	Submit the string as a suggestion; this works the same as pressing Suggest while editing translation.
`Ctrl` + `E` or `Cmd` + `E`	Focus on translation editor.
`Ctrl` + `U` or `Cmd` + `U`	Focus on comment editor.
`Ctrl` + `M` or `Cmd` + `M`	Shows Automatic suggestions tab.
`Ctrl` + `1` to `Ctrl` + `9` or `Cmd` + `1` to `Cmd` + `9`	Copies placeable of a given number from source string.
`Ctrl` + `M` followed by `1` to `9` or `Cmd` + `M` followed by `1` to `9`	Copy the machine translation of a given number to current translation.
`Ctrl` + `I` followed by `1` to `9` or `Cmd` + `I` followed by `1` to `9`	Ignore one item in the list of failing checks.
`Ctrl` + `J` or `Cmd` + `J`	Shows the Nearby strings tab.
`Ctrl` + `S` or `Cmd` + `S`	Focus on search field.
`Ctrl` + `O` or `Cmd` + `O`	Copy the source string.
`Ctrl` + `Y` or `Cmd` + `Y`	Toggle the Needs editing checkbox.
`→`	Browse the next translation string.
`←`	Browse the previous translation string.