[dpdk-dev] errors while working with dpdk cuckoo hash

[dpdk-dev] errors while working with dpdk cuckoo hash

[Shirley Avishour]

[-- Attachment #1: Type: text/plain, Size: 732 bytes --]

Hi,

I am running an application over dpdk ver 16.04.
My application massively inserting and deleting from a hash table using a
key that can be very similar for many instances.
I noticed that in some cases I am unable to find an entry while I am
certain it was inserted successfully.
I wrote a test to try and reproduce the problem and I have managed to
recreate the problem.
Attached is a c file containing the test which recreates the problem.
The key and hash function/hash size which I used in the test are identical
to what I use in my application.
attached is also a file containing the printouts of the test and indication
to 2 of the problems I encountered.
Are these known issues? is there a fix for that?

Thanks,
Shirley

[-- Attachment #2: cuckoo_hash_problem.txt --]
[-- Type: text/plain, Size: 2152 bytes --]

test iteration 0: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000
test iteration 1: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000

ALREADY EXISTS (VT 27, SID 0, SSN 6606, UBIT 0) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183) SIG 3111868123
NOT FOUND (VT 27, SID 0, SSN 6606, UBIT 0) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183)

test iteration 2: entry_misses 1, add_entry_fail 0, entry_hits 30001, entry_rm 77999, entry_add 77999
test iteration 3: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000
test iteration 4: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000

ADD (VT 56, SID 0, SSN 4444, UBIT 1) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183) SIG 777357509
NOT FOUND (VT 56, SID 0, SSN 4444, UBIT 1) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183)

test iteration 5: entry_misses 1, add_entry_fail 0, entry_hits 30000, entry_rm 77999, entry_add 78000
test iteration 6: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000
test iteration 7: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000
test iteration 8: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000
test iteration 9: entry_misses 0, add_entry_fail 0, entry_hits 30000, entry_rm 78000, entry_add 78000


============================================================================================================


test iteration 2:
(*) receiving an already exist message for the given key before inserting to the table.
ALREADY EXISTS (VT 27, SID 0, SSN 6606, UBIT 0) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183) SIG 3111868123
(*) when later performing lookup I get a not found message..
NOT FOUND (VT 27, SID 0, SSN 6606, UBIT 0) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183)


test iteration 5:
(*) entry insterted to the table and was not found when performing lookup:
ADD (VT 56, SID 0, SSN 4444, UBIT 1) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183) SIG 777357509
NOT FOUND (VT 56, SID 0, SSN 4444, UBIT 1) (DST 0xB5ABE6D5/64703, SRC 0xD5445A3E/7183)

Re: [dpdk-dev] errors while working with dpdk cuckoo hash

[De Lara Guarch, Pablo]

Hi Shirley,

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Shirley Avishour
> Sent: Monday, August 21, 2017 12:37 PM
> To: dev@dpdk.org
> Subject: [dpdk-dev] errors while working with dpdk cuckoo hash
> 
> Hi,
> 
> I am running an application over dpdk ver 16.04.
> My application massively inserting and deleting from a hash table using a
> key that can be very similar for many instances.
> I noticed that in some cases I am unable to find an entry while I am certain
> it was inserted successfully.
> I wrote a test to try and reproduce the problem and I have managed to
> recreate the problem.
> Attached is a c file containing the test which recreates the problem.
> The key and hash function/hash size which I used in the test are identical to
> what I use in my application.
> attached is also a file containing the printouts of the test and indication to 2
> of the problems I encountered.
> Are these known issues? is there a fix for that?

Could you attach the code? I only see the results, but not the C code.

Thanks,
Pablo

> 
> Thanks,
> Shirley

Re: [dpdk-dev] errors while working with dpdk cuckoo hash

[Shirley Avishour]

Hi Pablo,
Attached are 2 files. one which contains the results and the other is the c
code. I will attach the c file again.
I managed to recreate the problem after upgrading to stable version
dpdk-stable-16.11.2.
Thanks,
Shirley.


On Wed, Aug 30, 2017 at 3:37 PM, De Lara Guarch, Pablo <
pablo.de.lara.guarch@intel.com> wrote:

> Hi Shirley,
>
> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Shirley Avishour
> > Sent: Monday, August 21, 2017 12:37 PM
> > To: dev@dpdk.org
> > Subject: [dpdk-dev] errors while working with dpdk cuckoo hash
> >
> > Hi,
> >
> > I am running an application over dpdk ver 16.04.
> > My application massively inserting and deleting from a hash table using a
> > key that can be very similar for many instances.
> > I noticed that in some cases I am unable to find an entry while I am
> certain
> > it was inserted successfully.
> > I wrote a test to try and reproduce the problem and I have managed to
> > recreate the problem.
> > Attached is a c file containing the test which recreates the problem.
> > The key and hash function/hash size which I used in the test are
> identical to
> > what I use in my application.
> > attached is also a file containing the printouts of the test and
> indication to 2
> > of the problems I encountered.
> > Are these known issues? is there a fix for that?
>
> Could you attach the code? I only see the results, but not the C code.
>
> Thanks,
> Pablo
>
> >
> > Thanks,
> > Shirley
>