1. ONL Stats Engine
David M. Zar Applied Research Laboratory Computer Science and Engineering Department

2. Stats Engine
The Stats Engine will be a single ME devoted to accepting messages in a scratch ring and performing increment and add operations to counters.
All MEs that need to update counters will use the Stats Engine
Operations supported will be
Atomic increment (+1)
Atomic add (+data)
Format of the commands will be
Opcode(4b) Data (12b) Index (16b)

3. Opcodes Opcode – 0011 +1, +data pre-q counter specified in Index
Opcode(4b) Data (12b) Index (16b)
Opcode –
, +data pre-q counter specified in Index
, +data post-q counter specified in Index
pre-q counter specified in Index
post-q counter specified in Index
0001 +data pre-q counter specified in Index
0101 +data post-q counter specified in Index
, +data register specified in Index
register specified in Index

4. Stats Counters Each Index specifies a group of four counters
Pre-Q packet count
Pre-Q byte count
Post-Q packet count
Post-Q byte count
The packet counters get updated when the +1 instructions are specified (opcodes 0-1-)
The byte counter get updated when the +data instructions are specified (opcodes 0--1)
For plug-ins, the use for each counter can be redefined but the opcodes do not change (i.e. each stats index corresponds to two incrementers and two adders).

5. Stats Registers
For system-wide counters, we define a separate set of registers to handle them.
RX (packet and byte, 5 ports  10 words)
TX (packet and byte, 5 ports  10 words)
Drop counts (10 words)
Plug-in use (four per plug-in  20 words)
= 50 so reserve 64 words for these
The register gets incremented when the +1 instructions are specified (opcodes 101-)
The register gets added to updated when the +data instructions are specified (opcodes 10-1)
The RX and TX counters will be assigned on even-word boundaries (lsb = 0) so we associate the packet and byte coutners, together, and can do the +1, +data instruction on them in one command
For plug-ins, the allocation of each register is under the control of the plug-in.

6. ONL Router Counter Registers
// RX Per Port registers: (Updated by MUX)
ONL_ROUTER_RX_PORT0_PKT_CNTR
ONL_ROUTER_RX_PORT0_BYTE_CNTR
ONL_ROUTER_RX_PORT1_PKT_CNTR
ONL_ROUTER_RX_PORT1_BYTE_CNTR
ONL_ROUTER_RX_PORT2_PKT_CNTR
ONL_ROUTER_RX_PORT2_BYTE_CNTR
ONL_ROUTER_RX_PORT3_PKT_CNTR
ONL_ROUTER_RX_PORT3_BYTE_CNTR
ONL_ROUTER_RX_PORT4_PKT_CNTR
ONL_ROUTER_RX_PORT4_BYTE_CNTR
// TX Per Port registers: (Updated by HF)
ONL_ROUTER_TX_PORT0_PKT_CNTR
ONL_ROUTER_TX_PORT0_BYTE_CNTR
ONL_ROUTER_TX_PORT1_PKT_CNTR
ONL_ROUTER_TX_PORT1_BYTE_CNTR
ONL_ROUTER_TX_PORT2_PKT_CNTR
ONL_ROUTER_TX_PORT2_BYTE_CNTR
ONL_ROUTER_TX_PORT3_PKT_CNTR
ONL_ROUTER_TX_PORT3_BYTE_CNTR
ONL_ROUTER_TX_PORT4_PKT_CNTR
ONL_ROUTER_TX_PORT4_BYTE_CNTR
// IP Drop registers (Updated by PLC)
ONL_ROUTER_IP_HEC_DROP_CNTR
ONL_ROUTER_IP_LENGTH_ERR_DROP_CNTR
ONL_ROUTER_IP_HDR_LENGTH_ERR_DROP_CNTR
ONL_ROUTER_IP_VERSION_ERR_DROP_CNTR

7. ONL Router Counter Registers
// PLC Drop registers (Updated by Parse, Lookup or Copy)
ONL_ROUTER_PLC_TO_PLUGIN_DROP_CNTR
ONL_ROUTER_PLC_TO_XSCALE_DROP_CNTR
// QM Drop registers (Updated by QM)
ONL_ROUTER_QUEUE_OVERFLOW_DROP_CNTR
// XScale Drop registers (Updated by XScale)
ONL_ROUTER_XSCALE_DROP_CNTR
// Rx Drop registers (Updated by Rx)
ONL_ROUTER_RX__DROP_CNTR
// Tx Drop registers (Updated by Tx)
ONL_ROUTER_TX_DROP_CNTR
// Per Block Generic Error Counters
ONL_ROUTER_RX_GENERIC_ERROR_CNTR
ONL_ROUTER_MUX_GENERIC_ERROR_CNTR
ONL_ROUTER_PLC_GENERIC_ERROR_CNTR
ONL_ROUTER_QM_GENERIC_ERROR_CNTR
ONL_ROUTER_HF_GENERIC_ERROR_CNTR
ONL_ROUTER_TX_GENERIC_ERROR_CNTR
ONL_ROUTER_STATS_GENERIC_ERROR_CNTR
ONL_ROUTER_FREELISTMGR_GENERIC_ERROR_CNTR

8. ONL Router Counter Registers
// Plugin 0 Counters (for use however Plugin writer wants to use them)
ONL_ROUTER_PLUGIN_0_CNTR_0
ONL_ROUTER_PLUGIN_0_CNTR_1
ONL_ROUTER_PLUGIN_0_CNTR_2
ONL_ROUTER_PLUGIN_0_CNTR_3
// Plugin 2 Counters (for use however Plugin writer wants to use them)
ONL_ROUTER_PLUGIN_1_CNTR_0
ONL_ROUTER_PLUGIN_1_CNTR_1
ONL_ROUTER_PLUGIN_1_CNTR_2
ONL_ROUTER_PLUGIN_1_CNTR_3
ONL_ROUTER_PLUGIN_2_CNTR_0
ONL_ROUTER_PLUGIN_2_CNTR_1
ONL_ROUTER_PLUGIN_2_CNTR_2
ONL_ROUTER_PLUGIN_2_CNTR_3
// Plugin 3 Counters (for use however Plugin writer wants to use them)
ONL_ROUTER_PLUGIN_3_CNTR_0
ONL_ROUTER_PLUGIN_3_CNTR_1
ONL_ROUTER_PLUGIN_3_CNTR_2
ONL_ROUTER_PLUGIN_3_CNTR_3
// Plugin 4 Counters (for use however Plugin writer wants to use them)
ONL_ROUTER_PLUGIN_4_CNTR_0
ONL_ROUTER_PLUGIN_4_CNTR_1
ONL_ROUTER_PLUGIN_4_CNTR_2
ONL_ROUTER_PLUGIN_4_CNTR_3

9. Stats Counter Priority
There are two levels of priority for Stats Counters
High-priority (high-speed) are kept in local memory. There are 64 sets of counters for the router and 64 for the plug-ins
Low-priority (low-speed) are in SRAM. There are = of these.
Stats Counters point to the high-priority counters while are low-priority counters.
Using low-priority Stats Counters to count events that happen at high speed may degrade system performance (being a pre-Q counter on a high-priority queue, for example)
Plug-ins need to be aware of the segmentation of priority so they can use the proper priority counters based on needs
Stats Registers are always high-priority
One ME thread will be used to write 8W chunks of the local memory counters/registers to SRAM so that each counter/register is updated in SRAM several times a second.

10. Local Memory Map Status Registers 63 Reserved 64 12763
Reserved 64
127
Stats Counters (router)
64*4W = 256W
128
383
Stats Counters (plug-ins)
384
639