Short introduction

Pulsar Backends @ Parkes

Outline• PDFB – Single beam pulsar timing system• CASPER – Single beam pulsar coherent dedispersion system• BPSR – 13 beam pulsar, burst search system

PDFB: Pulsar Digital Filter Bank• Single pixel incoherent dedispersion using FPGAs• Hardware• 20p FPGAs• 1p server

• Software• FPGA based PFB

PDFB• PDFB’s sampler samples two polarization analog signals to 1 GSps with 10 bit, the data feeds into a reconfigurable PFB, after integration and folding for every channel, the data goes into a server where psrfits files are generated.

PDFBP0 / 1GSps

P1 / 1GSps

PFB ServerIntegration FoldingCorrelation

CASPSR: CASPER Parkes Swinburne Recorder• Single pixel phase-coherent dispersion removal using GPU• Hardware• 1p Interconnect Break-out Board (IBOB);• 1p Cisco® SFS 7000 InfiniBand Server Switch;• 2p Dell R610 demux Server Nodes, each with 48 GB of RAM; • 4p Supermicro® NITRO G5 Tesla GPU Compute Nodes, each

with dual quad-core Intel® Xeon E5520 (Nehalem-EP) processors, 24 GB of RAM, and 2 NVIDIA Tesla C1060 GPUs with 4GB of memory;• 2p 48T RAID storages.

• Software• routed, managed, and monitored using PSRDADA;• coherently dedispersed and reduced in real-time using DSPSR; • archived for later analysis using PSRCHIVE.

CASPSR• The IBOB performs analog-to-digital conversion of two dual-polarization signals, each with a maximum total bandwidth of 400 MHz. These signals are streamed via 2 × 10 GbE connections to the 2 R610 servers, which buffer the data and remultiplex the UDP packets to deliver contiguous streams to the 4 GPU-based processing nodes.• Every 8 seconds’ data folded into one profile or dumped as one baseband data file• Time resolution: 1.25e-9s, dynamic range: 8bit

IBOBDemux server 0

Demux server 1

CPU/GPU server 0

InfiniBandswitch

CPU/GPU server 3

CPU/GPU server 1

CPU/GPU server 2

800MB/s@10Gbps

1.6GB/s@20Gbps

20Gbps

RAID 0

800MB/s@10Gbps

0.8GB/s@20Gbps

P0 / 800MSps

P1 / 800MSps

20Gbps

RAID 1

CASPSR detailed data path• Analog signal converts to 800MSps digital data using IBOB• IBOB transfer the data to 2 demux servers via 2 10 GbE• Demux servers send data to 4 GPU-based servers via 20 Gb

InfiniBand• If baseband data recording• GPU servers write the unprocessed data to RAID

• Else real time coherent dedispersion• 512K FFT

• Multiply the chirp function

• 512 × 1K IFFT

• Detect

• Fold• Record

IBOBDemux server 0

Demux server 1

CPU/GPU server 0

InfiniBandswitch

CPU/GPU server 3

CPU/GPU server 1

CPU/GPU server 2

800MB/s@10Gbps

1.6GB/s@20Gbps

20Gbps

RAID 0

800MB/s@10Gbps

0.8GB/s@20Gbps

P0 / 800MSps

P1 / 800MSps

20Gbps

RAID 1

BPSR: Berkeley Parkes Swinburne Recorder• 13 pixel pulsar, burst search using GPU• Hardware• 13p Interconnect ROACH(IBOB);• 1p 20Gbps InfiniBand switch;• 7p 2 Tesla GPUs;• 2p 48T RAID storage.

• Software• routed, managed, and monitored using PSRDADA;• summed, normalized, decimated to 2 bits per sample, and

written to disk in real-time using DSPSR.

BPSR• The ROACH boards perform analog-to-digital conversion of two dual-polarization signals, each with a bandwidth of 400 MHz. • These signals are sub-divided into 1024 frequency channels using a polyphase filter bank, detected, integrated, decimated to 8 bits on ROACH, and streamed to 7 server-class nodes, each directly connected to a ROACH via 10 GbE CX4.• Time resolution: 32 microseconds, dynamic range: 2bit

ROACH 1B0 / P0 / 800MSps

B0 / P1 / 800MSps

ROACH 2B1 / P0 / 800MSps

B1 / P1 / 800MSps

CPU/GPU server 010Gbps

InfiniBandswitch

ROACH 13B13 / P0 / 800MSps

B13 / P1 / 800MSpsCPU/GPU server 7

10Gbps

... ... RAID 0

RAID 120Gbps

BPSR detailed data path• Analog signal converts to 800MSps digital data using ROACH

for every pixel• ROACH makes 1024-channel polyphase filter bank, detects,

integrates every channel for a few microseconds and decimates to 8 bits• Every two pixels’ data is sent to one server with 2 GPUs• GPU does real time DM search• GPU servers write the integrated, normalized, decimated to 2

bits data to RAIDROACH 1B0 / P0 / 800MSps

B0 / P1 / 800MSps

ROACH 2B1 / P0 / 800MSps

B1 / P1 / 800MSps

CPU/GPU server 010Gbps

InfiniBandswitch

ROACH 13B13 / P0 / 800MSps

B13 / P1 / 800MSpsCPU/GPU server 7

10Gbps

... ... RAID 0

RAID 120Gbps

Thank you!