Thanks ron for looking into this.

On Tue, Oct 6, 2015 at 3:17 PM, Ron Economos <[email protected]> wrote:

> It's actually trying to allocate 3 GBytes, which seems huge. You may not
> have enough free memory. I would try to determine what change you made
> that's causing such a large allocation.
>
> An FFT size of 2048 is still pretty small. In the DVB-T2 OFDM transmitter,
> even with a 16384 FFT size, it's only using 52 MBytes of shared memory.
>
> Ron
>
>
> On 10/06/2015 12:30 AM, Hitesh Kasera wrote:
>
> At first i tried that one only but that didn't work out. Then i tried to
> set shared memory 8GB. The syntax i used the same
> sudo sysctl kernel.shmmax=8589934592 but still getting the same error.
>
> Hitesh
>
>
>
> On Tue, Oct 6, 2015 at 10:51 AM, Ron Economos <[email protected]> wrote:
>
>> The correct syntax is:
>>
>> sudo sysctl kernel.shmmax=2147483648
>>
>> for 2 Gbytes.
>>
>> Ron
>>
>>
>> On 10/05/2015 10:01 PM, Hitesh Kasera wrote:
>>
>>> Hello everyone,
>>> I am trying to implement OFDM TX in GRC but with fft length 2048.
>>> according to fft length i have updated syn words, pilot carriers, pilot
>>> symbols, occupied carriers. When i run the flow graph i get this error:
>>>
>>> gr::vmcircbuf_sysv_shm: shmget (1): Invalid argument
>>> gr::vmcircbuf_sysv_shm: shmget (1): Invalid argument
>>> gr::vmcircbuf_sysv_shm: shmget (1): Invalid argument
>>> gr::buffer::allocate_buffer: failed to allocate buffer of size 1536000 KB
>>> gr::vmcircbuf_sysv_shm: shmget (1): Invalid argument
>>> gr::vmcircbuf_sysv_shm: shmget (1): Invalid argument
>>> gr::vmcircbuf_sysv_shm: shmget (1): Invalid argument
>>> gr::buffer::allocate_buffer: failed to allocate buffer of size 1536000 KB
>>> terminate called after throwing an instance of 'std::bad_alloc'
>>> what(): std::bad_alloc
>>>
>>> Buffer size is around 1.5GB. i tried to set kernel.shmmax to 8GB but its
>>> not working. I am using Ubuntu 14.04. Kernel and GNU details are:
>>> GNU Radio Companion 3.7.8rc1
>>> GNU C++ version 4.8.4
>>> UHD_003.009.git-217-g012381d9
>>> kernel release - 3.13.0-58-generic
>>> kernel version - #97-Ubuntu SMP
>>>
>>> I am new to work with GNU Radio. I am not able to correct this error. If
>>> anyone has any idea to correct this please tell me.
>>>
>>> Best Regards
>>> Hitesh
>>>
>>>
>>>
>> _______________________________________________
>> Discuss-gnuradio mailing list
>> [email protected]
>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>
>
>
>
> _______________________________________________
> Discuss-gnuradio mailing list
> [email protected]
> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>
>
_______________________________________________
Discuss-gnuradio mailing list
[email protected]
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

Reply via email to