xref: /dpdk/doc/guides/linux_gsg/linux_eal_parameters.rst (revision 0dff3f26d6faad4e51f75e5245f0387ee9bb0c6d)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2018 Intel Corporation.
3
4EAL parameters
5==============
6
7This document contains a list of all EAL parameters. These parameters can be
8used by any DPDK application running on Linux.
9
10Common EAL parameters
11---------------------
12
13The following EAL parameters are common to all platforms supported by DPDK.
14
15.. include:: eal_args.include.rst
16
17Linux-specific EAL parameters
18-----------------------------
19
20In addition to common EAL parameters, there are also Linux-specific EAL
21parameters.
22
23Device-related options
24~~~~~~~~~~~~~~~~~~~~~~
25
26*   ``--create-uio-dev``
27
28    Create ``/dev/uioX`` files for devices bound to igb_uio kernel driver
29    (usually done by the igb_uio driver itself).
30
31*   ``--vmware-tsc-map``
32
33    Use VMware TSC map instead of native RDTSC.
34
35*   ``--no-hpet``
36
37    Do not use the HPET timer.
38
39*   ``--vfio-intr <legacy|msi|msix>``
40
41    Use specified interrupt mode for devices bound to VFIO kernel driver.
42
43*   ``--vfio-vf-token <uuid>``
44
45    Use specified VF token for devices bound to VFIO kernel driver.
46
47Multiprocessing-related options
48~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
49
50*   ``--file-prefix <prefix name>``
51
52    Use a different shared data file prefix for a DPDK process. This option
53    allows running multiple independent DPDK primary/secondary processes under
54    different prefixes.
55
56Memory-related options
57~~~~~~~~~~~~~~~~~~~~~~
58
59*   ``--legacy-mem``
60
61    Use legacy DPDK memory allocation mode.
62
63*   ``--socket-mem <amounts of memory per socket>``
64
65    Preallocate specified amounts of memory per socket. The parameter is a
66    comma-separated list of values. For example::
67
68        --socket-mem 1024,2048
69
70    This will allocate 1 gigabyte of memory on socket 0, and 2048 megabytes of
71    memory on socket 1.
72
73*   ``--socket-limit <amounts of memory per socket>``
74
75    Place a per-socket upper limit on memory use (non-legacy memory mode only).
76    0 will disable the limit for a particular socket.
77
78*   ``--single-file-segments``
79
80    Create fewer files in hugetlbfs (non-legacy mode only).
81
82*   ``--huge-dir <path to hugetlbfs directory>``
83
84    Use specified hugetlbfs directory instead of autodetected ones. This can be
85    a sub-directory within a hugetlbfs mountpoint.
86
87*   ``--huge-unlink[=existing|always|never]``
88
89    No ``--huge-unlink`` option or ``--huge-unlink=existing`` is the default:
90    existing hugepage files are removed and re-created
91    to ensure the kernel clears the memory and prevents any data leaks.
92
93    With ``--huge-unlink`` (no value) or ``--huge-unlink=always``,
94    hugepage files are also removed before mapping them,
95    so that the application leaves no files in hugetlbfs.
96    This mode implies no multi-process support.
97
98    When ``--huge-unlink=never`` is specified, existing hugepage files
99    are never removed, but are remapped instead, allowing hugepage reuse.
100    This makes restart faster by saving time to clear memory at initialization,
101    but it may slow down zeroed allocations later.
102    Reused hugepages can contain data from previous processes that used them,
103    which may be a security concern.
104    Hugepage files created in this mode are also not removed
105    when all the hugepages mapped from them are freed,
106    which allows to reuse these files after a restart.
107
108*   ``--match-allocations``
109
110    Free hugepages back to system exactly as they were originally allocated.
111
112Other options
113~~~~~~~~~~~~~
114
115*   ``--syslog <syslog facility>``
116
117    Set syslog facility. Valid syslog facilities are::
118
119        auth
120        cron
121        daemon
122        ftp
123        kern
124        lpr
125        mail
126        news
127        syslog
128        user
129        uucp
130        local0
131        local1
132        local2
133        local3
134        local4
135        local5
136        local6
137        local7
138