Re: [dpdk-users] Run testpmd application and encountered no free page issues

[Paul Tsvika <mozloverinweb@gmail.com>]

Hi Shreransh,

Inline [PT02],





2017-06-21 13:35 GMT+08:00 Shreyansh Jain <shreyansh.jain@nxp.com>:

> Hi Paul,
>
> Inline, with [SJ02]
>
> From: Paul Tsvika [mailto:mozloverinweb@gmail.com]
> Sent: Wednesday, June 21, 2017 8:47 AM
> To: Shreyansh Jain <shreyansh.jain@nxp.com>
> Cc: users@dpdk.org
> Subject: Re: [dpdk-users] Run testpmd application and encountered no free
> page issues
>
> Thanks Shreyansh.
>
> My comment prepended with [P01]
>
>
> 2017-06-20 19:10 GMT+08:00 Shreyansh Jain <mailto:shreyansh.jain@nxp.com>:
> Hello Paul,
>
> Some comments inline, prepended with [SJ01]:
> (Would it be possible for you to send text mails to this mailing list - it
> helps in keeping replies contextual)
>
> From: Paul Tsvika [mailto:mailto:mozloverinweb@gmail.com]
> Sent: Tuesday, June 20, 2017 2:27 PM
> To: Shreyansh Jain <mailto:shreyansh.jain@nxp.com>
> Cc: mailto:users@dpdk.org
> Subject: Re: [dpdk-users] Run testpmd application and encountered no free
> page issues
>
> Hi Shreyansh,
>
> Thanks for the reply.
>
> By using the set-up script in DPDK:
>
> the hugepage memory looks to be allocated properly:
>
> cat /proc/meminfo
>
> HugePages_Total:     240
> HugePages_Free:     240
> HugePages_Rsvd:        0
> HugePages_Surp:         0
> Hugepagesize:       2048 kB
>
>
> and then i run the commands below in sequence:
>
> $ sudo modprobe uio
> $ sudo insmod ./build/kmod/igb_uio.ko
> $ sudo ./usertools/dpdk-devbind.py -b igb_uio xxx:xx.0 xxx:xx.1   (
> xxx.xx.0, xxx.xx.1 <-- 10G port pci address )
> $ sudo ./build/app/testpmd -l 1,2,3 -n 2 -- -i
>
> EAL: Detected 16 lcore(s)
> EAL: No free hugepages reported in hugepages-1048576kB
>
> [SJ01] DPDK iterates over all directories in /sys/kernel/mm/hugepages
> which contains one directory for each supported hugepage size. This log
> above is appearing because nothing was found for a directory named
> "hugepages-1048576kB". That is probably because you have '0' hugepages of
> size 1G in your system. This should not impact you until you are were
> expecting 1G hugepage size.
>
> EAL: Probing VFIO support...
> EAL: VFIO support initialized
> EAL: PCI device 0000:03:00.0 on NUMA socket 0
> EAL:   probe driver: 8086:15ad net_ixgbe
> EAL: PCI device 0000:03:00.1 on NUMA socket 0
> EAL:   probe driver: 8086:15ad net_ixgbe
> EAL: PCI device 0000:05:00.0 on NUMA socket 0
> EAL:   probe driver: 8086:1521 net_e1000_igb
> EAL: PCI device 0000:05:00.1 on NUMA socket 0
> EAL:   probe driver: 8086:1521 net_e1000_igb
> Interactive-mode selected
> USER1: create a new mbuf pool <mbuf_pool_socket_0>: n=163456, size=2176,
> socket=0
> Configuring Port 0 (socket 0)
> PMD: ixgbe_dev_link_status_print():  Port 0: Link Down
> Port 0: 00:25:90:5C:E9:58
> Configuring Port 1 (socket 0)
> PMD: ixgbe_dev_link_status_print():  Port 1: Link Down
> Port 1: 00:25:90:5C:E9:59
> Checking link statuses...
> Done
> testpmd>
>
>
> Questions below:
>
> 1. It looks like the application can enter the interactive mode. however,
> I have no idea why EAL: No free hugepages reported in hugepages-1048576kB
> keeps popping out.
>
> [SJ01] Lets ignore that for while. You have about 240 pages of 2M =
> ~480Mb. Application is demanding ~339Mb (n=163456, size=2176)
>
>
> 2. Is there any reason why the ports went down why I run the commands? The
> Link was up before running it.
>
> [SJ01] This I am not sure. If the links were up _before_, they should be
> up now as well. Just out of curiosity, how did you check that links were up
> before? These links are not assigned to Linux kernel and are not visible in
> the ifconfig list.
>
> [P01] I don't know why you mentioned that these links are not assigned to
> Linux kernel and not visible in the ifconfig list. ixgbe is the inbox
> driver of the kernel and eno3 and eno4 ( 10G ports ) appear in ifconfig
> list.
> However, eno3 and eno4 gone away ( disappeared in ifconfig ) when running
> this command. I am still investigating the issue.
>
> [SJ02] That is not an issue. That is how it is supposed to work. When you
> start DPDK, it would unlink the devices from their standard ixgbe kernel
> module driver and link to uio/vfio driver for direct userspace interaction.
> That is the reason these links would not appear in ifconfig list – and that
> is the right way. Were you able to use these links when they were bound to
> ixgbe kernel module - that is, ping worked before DPDK was started?
>
> [PT02]
>

You are correct. For some reasons that my 10G ports on board A did not work
even before running DPDK.
After changing a new board and run the steps mentioned above, it worked.
Thank you for the discussion in this mail thread.

>
> 3. The hugepage will be gone after running this application.
>
> HugePages_Total:     240
> HugePages_Free:         0
> HugePages_Rsvd:        0
> HugePages_Surp:         0
> Hugepagesize:       2048 kB
>
> It became this. However, how can i free it again ? I tried to umount and
> mount again but it did not work.
>
> [SJ01] Just go and delete all files created in /mnt/hugepages/ folder. You
> would have "HugePages_Free" available again. But, only if you have the
> application stopped.
>
>
> Please advice if any.
>
> [SJ01] Above is all what I know. I have no idea why your links are
> appearing down.
>
> -
> Shreyansh
>
>
>
>
> Paul
> --
> P.T
>



-- 
P.T