Chapter 2
X3 Migration Quickstart
Read this Quickstart if you are migrating to the X3522 adapter from its predecessors that were
designed by Solarflare, such as the 7000-series, 8000-series and XtremeScale X2-series. It
outlines the major differences between the X3522 and its predecessors, and where to find out
more:
Reduced Latency
• ½ RTT latency for an X3522 is about 230 ns lower than for an X2522, measured using
eflatency with a 200 byte packet over PCIe
®
Gen4 and 10 GbE.
• The X3522 has been optimized for PCIe Gen4. Using PCIe Gen3 instead of Gen4 incurs a
½ RTT penalty of >80 ns.
See the Onload User Guide (
) for full details of test setup, and for comprehensive latency
values and graphs.
New RX and TX Data Path Designs
• RX queues are managed by the driver and are shared between applications. Applications that
share a queue should run on cores that share their L3 cache. Explicit huge pages are required.
• TX always uses CTPIO, with 16 apertures per port instead of the single aperture used by the
X2-series, allowing senders to have a dedicated aperture. This and other design improvements
have made CTPIO more robust.
See
.
New Drivers and Software Packages
• The X3522 uses a new Linux net driver named
xilinx_efct
, supplied separately from
Onload.
• The X3522 also uses the auxiliary bus driver. This is provided by some recent Linux
distributions, or can be downloaded from Xilinx.
• TCPDirect is now supplied in its own package, separately from Onload.
See the Alveo X3522 Installation Guide (
), the Onload User Guide (
) and the
TCPDirect User Guide (
Chapter 2: X3 Migration Quickstart
UG1523 (v1.0) October 18, 2022
Alveo X3522 User Guide
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