2 title: "Per Thread Resources"
8 CSIT test framework is managing mapping of the following resources per
11 1. Cores, physical cores (pcores) allocated as pairs of sibling logical cores
12 (lcores) if server in HyperThreading/SMT mode, or as single lcores
13 if server not in HyperThreading/SMT mode. Note that if server's
14 processors are running in HyperThreading/SMT mode sibling lcores are
16 2. Receive Queues (RxQ), packet receive queues allocated on each
17 physical and logical interface tested.
18 3. Transmit Queues(TxQ), packet transmit queues allocated on each
19 physical and logical interface tested.
21 Approach to mapping per thread resources depends on the application/DUT
22 tested (VPP or DPDK apps) and associated thread types, as follows:
24 1. Data-plane workers, used for data-plane packet processing, when no
25 feature workers present.
27 - Cores: data-plane workers are typically tested in 1, 2 and 4 pcore
28 configurations, running on single lcore per pcore or on sibling
29 lcores per pcore. Result is a set of {T}t{C}c thread-core
30 configurations, where{T} stands for a total number of threads
31 (lcores), and {C} for a total number of pcores. Tested
32 configurations are encoded in CSIT test case names,
33 e.g. "1c", "2c", "4c", and test tags "2T1C"(or "1T1C"), "4T2C"
34 (or "2T2C"), "8T4C" (or "4T4C").
35 - Interface Receive Queues (RxQ): as of CSIT-2106 release, number of
36 RxQs used on each physical or virtual interface is equal to the
37 number of data-plane workers. In other words each worker has a
38 dedicated RxQ on each interface tested. This ensures packet
39 processing load to be equal for each worker, subject to RSS flow
40 load balancing efficacy. Note: Before CSIT-2106 total number of
41 RxQs across all interfaces of specific type was equal to the
42 number of data-plane workers.
43 - Interface Transmit Queues (TxQ): number of TxQs used on each
44 physical or virtual interface is equal to the number of data-plane
45 workers. In other words each worker has a dedicated TxQ on each
47 - Applies to VPP and DPDK Testpmd and L3Fwd.
49 2. Data-plane and feature workers (e.g. IPsec async crypto workers), the
50 latter dedicated to specific feature processing.
52 - Cores: data-plane and feature workers are tested in 2, 3 and 4
53 pcore configurations, running on single lcore per pcore or on
54 sibling lcores per pcore. This results in a two sets of
55 thread-core combinations separated by "-", {T}t{C}c-{T}t{C}c, with
56 the leading set denoting total number of threads (lcores) and
57 pcores used for data-plane workers, and the trailing set denoting
58 total number of lcores and pcores used for feature workers.
59 Accordingly, tested configurations are encoded in CSIT test case
60 names, e.g. "1c-1c", "1c-2c", "1c-3c", and test tags "2T1C_2T1C"
61 (or "1T1C_1T1C"), "2T1C_4T2C"(or "1T1C_2T2C"), "2T1C_6T3C"
63 - RxQ and TxQ: no RxQs and no TxQs are used by feature workers.
64 - Applies to VPP only.
66 3. Management/main worker, control plane and management.
68 - Cores: single lcore.
69 - RxQ: not used (VPP default behaviour).
70 - TxQ: single TxQ per interface, allocated but not used
71 (VPP default behaviour).
72 - Applies to VPP only.
74 ## VPP Thread Configuration
76 Mapping of cores and RxQs to VPP data-plane worker threads is done in
77 the VPP startup.conf during test suite setup:
79 1. `corelist-workers <list_of_cores>`: List of logical cores to run VPP
80 data-plane workers and feature workers. The actual lcores'
81 allocations depends on HyperThreading/SMT server configuration and
82 per test core configuration.
84 - For tests without feature workers, by default, all CPU cores
85 configured in startup.conf are used for data-plane workers.
86 - For tests with feature workers, CSIT code distributes lcores across
87 data-plane and feature workers.
89 2. `num-rx-queues <value>`: Number of Rx queues used per interface.
91 Mapping of TxQs to VPP data-plane worker threads uses the default VPP
92 setting of one TxQ per interface per data-plane worker.
94 ## DPDK Thread Configuration
96 Mapping of cores and RxQs to DPDK Testpmd/L3Fwd data-plane worker
97 threads is done in the startup CLI:
99 1. `-l <list_of_cores>` - List of logical cores to run DPDK
101 2. `nb-cores=<N>` - Number of forwarding cores.
102 3. `rxq=<N>` - Number of Rx queues used per interface.