On 8/6/21 2:44 PM, Rosemarie O'Riorden wrote:
> If anonymous memory mapping is supported by the kernel, it's better
> to run OVS entirely in memory rather than creating shared data
> structures. OVS doesn't work in multi-process mode, so there is no need
> to litter a filesystem and experience random crashes due to old memory
> chunks stored in re-opened files.
>
> When OVS is not running in memory and crashes, it never reaches the
> clean up scripts that delete the new files it has created, resulting in
> "dirty" memory. OVS will partially overwrite this memory on the next
> start-up, but will fail to run again because its filesystem is full of
> old memory.
>
> Here is an example of these crashes:
> https://inbox.dpdk.org/dev/[email protected]/
>
> Reported at: https://bugzilla.redhat.com/show_bug.cgi?id=1949849
> Signed-off-by: Rosemarie O'Riorden <[email protected]>
> ---
Thanks for the patch!
Anonymous hugepage mapping is supported starting from 3.8 kernel, and
the oldest longterm upstream kernel currently is 4.4, so it should be
supported in any modern system. It's nice to have a compile time check
though. So we're good here.
We also removed from OVS all the features that required support for
multi-process mode (pdump and ring ports), so it should be safe to
use --in-memory.
All in all, beside the trailing whitespace warning, the patch looks
good to me.
Ian, what do you think?
Best regards, Ilya Maximets.
> NEWS | 1 +
> acinclude.m4 | 6 ++++++
> lib/dpdk.c | 7 +++++++
> 3 files changed, 14 insertions(+)
>
> diff --git a/NEWS b/NEWS
> index 26920e215..515d3cddd 100644
> --- a/NEWS
> +++ b/NEWS
> @@ -8,6 +8,7 @@ Post-v2.16.0
> by default. 'other_config:dpdk-socket-limit' can be set equal to
> the 'other_config:dpdk-socket-mem' to preserve the legacy memory
> limiting behavior.
> + * EAL argument --in-memory is applied by default if supported.
>
>
> v2.16.0 - xx xxx xxxx
> diff --git a/acinclude.m4 b/acinclude.m4
> index 5a48f0335..7720f2f1b 100644
> --- a/acinclude.m4
> +++ b/acinclude.m4
> @@ -448,6 +448,12 @@ AC_DEFUN([OVS_CHECK_DPDK], [
> ], [[#include <rte_config.h>]])
> ], [], [[#include <rte_config.h>]])
>
> + AC_CHECK_DECL([MAP_HUGE_SHIFT], [
> + AC_DEFINE([DPDK_IN_MEMORY_SUPPORTED], [1], [If MAP_HUGE_SHIFT is
> + defined, anonomous memory mapping is supported by the
> + kernel, and --in-memory can be used.])
> + ], [], [[#include <sys/mman.h>]])
> +
> # DPDK uses dlopen to load plugins.
> OVS_FIND_DEPENDENCY([dlopen], [dl], [libdl])
>
> diff --git a/lib/dpdk.c b/lib/dpdk.c
> index b2ef31cd2..97c902fab 100644
> --- a/lib/dpdk.c
> +++ b/lib/dpdk.c
> @@ -405,6 +405,13 @@ dpdk_init__(const struct smap *ovs_other_config)
> svec_add(&args, ovs_get_program_name());
> construct_dpdk_args(ovs_other_config, &args);
>
> +#ifdef DPDK_IN_MEMORY_SUPPORTED
> + if (!args_contains(&args, "--in-memory") &&
> + !args_contains(&args, "--legacy-mem")) {
> + svec_add(&args, "--in-memory");
> + }
> +#endif
> +
> if (args_contains(&args, "-c") || args_contains(&args, "-l")) {
> auto_determine = false;
> }
>
_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev
