- Each element of a bytemap is a scalar of the same type and the same length.
- The index of the first element of a bytemap is
0. - The index of any other element is the index of the previous element plus one.
- A default value is assigned to all the elements that have not been assigned yet.
- The internal representation of a bytemap is a string.
In the tables that follow, array is the native PHP array, SPL stands for \SplFixedArray and DS stands for \Ds\Sequence (i.e. \Ds\Deque and \Ds\Vector; with ext-ds).
| Element length | array | SPL | DS | Bytemap |
|---|---|---|---|---|
| 1 | 4.0 MB | 1.5 MB | 2.0 MB | 0.1 MB |
| 4 | 4.0 MB | 1.5 MB | 2.0 MB | 0.4 MB |
Data for 100,000 elements.
| Operation | array | SPL | DS | Bytemap |
|---|---|---|---|---|
foreach |
1.0 | 1.7 | 1.5 | 3.1 |
| pop | 1.0 | 1.6 | 1.2 | 32.2 |
| push | 1.0 | 1.7 | 1.3 | 3.3 |
| random read | 1.2 | 1.0 | 1.0 | 2.2 |
| random write | 1.1 | 1.0 | 1.3 | 2.4 |
| shift | 1.0 | N/A | *1.6 | 6.6 |
| unshift | 6405.9 | N/A | **1.0 | 22.1 |
\serialize |
104.9 | 140.5 | 62.0 | 1.0 |
\unserialize |
109.3 | 182.6 | 52.1 | 1.0 |
Data for 100,000 single-byte elements.
How to read this table: foreach over a bytemap takes 3.1 times the time it takes to iterate over an array with the same 100,000 single-byte elements.
* Data for \Ds\Deque (in this test, \Ds\Vector took 40.8 times the time it took to shift using \Ds\Deque).
** Data for \Ds\Deque (in this test, \Ds\Vector took 216.2 times the time it took to unshift using \Ds\Deque).
| Operation | array | SPL | DS | Bytemap |
|---|---|---|---|---|
| delete at head | 374.9 | 858.2 | 85.9 | 1.0 |
| delete at tail | 1032.9 | 1.0 | 12.0 | 2.6 |
| insert at head | 23.5 | 74.1 | *1.0 | 1.9 |
| insert at tail | 1.8 | 1.9 | 1.0 | 2.5 |
Deleted and (in a separate test) inserted a sequence of batches containing 1 to 1000 single-byte elements. The same sequence of batches was used for every benchmarked container. The sequence had 50,606 elements in total.
* Data for \Ds\Deque (in this test, \Ds\Vector took 1.5 times the time it took to insert at head using \Ds\Deque).
| Operation | Elements sought | array | SPL | DS | Bytemap |
|---|---|---|---|---|---|
| existence check | 1 out of 1 | 1.0 | 5.0 | 1.0 | 5.0 |
| existence check | 1 out of 10 | 1.0 | 1.7 | 1.4 | 1.8 |
| existence check | 100 out of 100 | 14.5 | 40.5 | 33.1 | 1.0 |
| find first index | 1 out of 1 | 1.1 | 5.9 | 1.0 | 4.5 |
| find all indexes | 100 out of 100 | 1.0 | 1.4 | 1.2 | 1.4 |
| grep | 100 out of 100 | 1.0 | 1.8 | 1.7 | 1.7 |
Data for 100,000 single-byte elements.
| Operation | Element count | Element length | Time |
|---|---|---|---|
| parsing | 100,000 | 1 | 0.02 s |
| parsing | 100,000 | 4 | 0.02 s |
| parsing | 1,000,000 | 1 | 0.19 s |
| parsing | 1,000,000 | 4 | 0.24 s |
| streaming | 100,000 | 1 | 0.01 s |
| streaming | 100,000 | 4 | 0.02 s |
| streaming | 1,000,000 | 1 | 0.10 s |
| streaming | 1,000,000 | 4 | 0.15 s |
Data for bytemaps only.
Parsing performed using the built-in JSON parser (\json_decode).
Robert Gust-Bardon - [email protected] - https://twitter.com/RGustBardon
Bytemap is licensed under the MIT License - see the LICENSE file for details.