1# free<a name="EN-US_TOPIC_0000001133846472"></a> 2 3- [Command Function](#section175151514841) 4- [Syntax](#section8488721749) 5- [Parameters](#section27272181949) 6- [Usage](#section148661259410) 7- [Example](#section68081530242) 8- [Output](#section171235517543) 9 10## Command Function<a name="section175151514841"></a> 11 12This command is used to display the system memory usage and the sizes of the **text**, **data**, **rodata**, and **bss** segments. 13 14## Syntax<a name="section8488721749"></a> 15 16free \[_-k | -m_\] 17 18## Parameters<a name="section27272181949"></a> 19 20**Table 1** Parameter description 21 22<a name="table110mcpsimp"></a> 23<table><thead align="left"><tr id="row116mcpsimp"><th class="cellrowborder" valign="top" width="21%" id="mcps1.2.4.1.1"><p id="p118mcpsimp"><a name="p118mcpsimp"></a><a name="p118mcpsimp"></a>Parameter</p> 24</th> 25<th class="cellrowborder" valign="top" width="52%" id="mcps1.2.4.1.2"><p id="p120mcpsimp"><a name="p120mcpsimp"></a><a name="p120mcpsimp"></a>Description</p> 26</th> 27<th class="cellrowborder" valign="top" width="27%" id="mcps1.2.4.1.3"><p id="p122mcpsimp"><a name="p122mcpsimp"></a><a name="p122mcpsimp"></a>Value Range</p> 28</th> 29</tr> 30</thead> 31<tbody><tr id="row123mcpsimp"><td class="cellrowborder" valign="top" width="21%" headers="mcps1.2.4.1.1 "><p id="p125mcpsimp"><a name="p125mcpsimp"></a><a name="p125mcpsimp"></a>No parameter</p> 32</td> 33<td class="cellrowborder" valign="top" width="52%" headers="mcps1.2.4.1.2 "><p id="p127mcpsimp"><a name="p127mcpsimp"></a><a name="p127mcpsimp"></a>Displays the size in bytes.</p> 34</td> 35<td class="cellrowborder" valign="top" width="27%" headers="mcps1.2.4.1.3 "><p id="p129mcpsimp"><a name="p129mcpsimp"></a><a name="p129mcpsimp"></a>N/A</p> 36</td> 37</tr> 38<tr id="row130mcpsimp"><td class="cellrowborder" valign="top" width="21%" headers="mcps1.2.4.1.1 "><p id="p132mcpsimp"><a name="p132mcpsimp"></a><a name="p132mcpsimp"></a>-k</p> 39</td> 40<td class="cellrowborder" valign="top" width="52%" headers="mcps1.2.4.1.2 "><p id="p134mcpsimp"><a name="p134mcpsimp"></a><a name="p134mcpsimp"></a>Displays the size in KiB.</p> 41</td> 42<td class="cellrowborder" valign="top" width="27%" headers="mcps1.2.4.1.3 "><p id="p136mcpsimp"><a name="p136mcpsimp"></a><a name="p136mcpsimp"></a>N/A</p> 43</td> 44</tr> 45<tr id="row137mcpsimp"><td class="cellrowborder" valign="top" width="21%" headers="mcps1.2.4.1.1 "><p id="p139mcpsimp"><a name="p139mcpsimp"></a><a name="p139mcpsimp"></a>-m</p> 46</td> 47<td class="cellrowborder" valign="top" width="52%" headers="mcps1.2.4.1.2 "><p id="p141mcpsimp"><a name="p141mcpsimp"></a><a name="p141mcpsimp"></a>Displays the size in MiB.</p> 48</td> 49<td class="cellrowborder" valign="top" width="27%" headers="mcps1.2.4.1.3 "><p id="p143mcpsimp"><a name="p143mcpsimp"></a><a name="p143mcpsimp"></a>N/A</p> 50</td> 51</tr> 52</tbody> 53</table> 54 55## Usage<a name="section148661259410"></a> 56 57None 58 59## Example<a name="section68081530242"></a> 60 61Run **free**, **free -k**, and **free -m**, respectively. 62 63## Output<a name="section171235517543"></a> 64 65**Figure 1** Displaying the memory usage in three units<a name="fig478715471421"></a> 66 67 68**Table 2** Output 69 70<a name="table633mcpsimp"></a> 71<table><thead align="left"><tr id="row638mcpsimp"><th class="cellrowborder" valign="top" width="50%" id="mcps1.2.3.1.1"><p id="p640mcpsimp"><a name="p640mcpsimp"></a><a name="p640mcpsimp"></a>Output</p> 72</th> 73<th class="cellrowborder" valign="top" width="50%" id="mcps1.2.3.1.2"><p id="p642mcpsimp"><a name="p642mcpsimp"></a><a name="p642mcpsimp"></a>Description</p> 74</th> 75</tr> 76</thead> 77<tbody><tr id="row643mcpsimp"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p645mcpsimp"><a name="p645mcpsimp"></a><a name="p645mcpsimp"></a>total</p> 78</td> 79<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p647mcpsimp"><a name="p647mcpsimp"></a><a name="p647mcpsimp"></a>Total size of the dynamic memory pool</p> 80</td> 81</tr> 82<tr id="row648mcpsimp"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p650mcpsimp"><a name="p650mcpsimp"></a><a name="p650mcpsimp"></a>used</p> 83</td> 84<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p652mcpsimp"><a name="p652mcpsimp"></a><a name="p652mcpsimp"></a>Size of the used memory</p> 85</td> 86</tr> 87<tr id="row653mcpsimp"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p655mcpsimp"><a name="p655mcpsimp"></a><a name="p655mcpsimp"></a>free</p> 88</td> 89<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p657mcpsimp"><a name="p657mcpsimp"></a><a name="p657mcpsimp"></a>Size of the unallocated memory</p> 90</td> 91</tr> 92<tr id="row658mcpsimp"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p660mcpsimp"><a name="p660mcpsimp"></a><a name="p660mcpsimp"></a>heap</p> 93</td> 94<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p662mcpsimp"><a name="p662mcpsimp"></a><a name="p662mcpsimp"></a>Size of the allocated heap</p> 95</td> 96</tr> 97<tr id="row10101624938"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p610724734"><a name="p610724734"></a><a name="p610724734"></a>text</p> 98</td> 99<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p1510024539"><a name="p1510024539"></a><a name="p1510024539"></a>Size of a code segment</p> 100</td> 101</tr> 102<tr id="row207288271839"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p572872713317"><a name="p572872713317"></a><a name="p572872713317"></a>data</p> 103</td> 104<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p272852716315"><a name="p272852716315"></a><a name="p272852716315"></a>Size of a data segment</p> 105</td> 106</tr> 107<tr id="row1774316321731"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p274343218317"><a name="p274343218317"></a><a name="p274343218317"></a>rodata</p> 108</td> 109<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p1974319321133"><a name="p1974319321133"></a><a name="p1974319321133"></a>Size of a read-only data segment</p> 110</td> 111</tr> 112<tr id="row121618371536"><td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.1 "><p id="p0161183720314"><a name="p0161183720314"></a><a name="p0161183720314"></a>bss</p> 113</td> 114<td class="cellrowborder" valign="top" width="50%" headers="mcps1.2.3.1.2 "><p id="p09295155511"><a name="p09295155511"></a><a name="p09295155511"></a>Size of the memory occupied by uninitialized global variables</p> 115</td> 116</tr> 117</tbody> 118</table> 119 120
