1/* 2 * linux/include/linux/sunrpc/metrics.h 3 * 4 * Declarations for RPC client per-operation metrics 5 * 6 * Copyright (C) 2005 Chuck Lever <cel@netapp.com> 7 * 8 * RPC client per-operation statistics provide latency and retry 9 * information about each type of RPC procedure in a given RPC program. 10 * These statistics are not for detailed problem diagnosis, but simply 11 * to indicate whether the problem is local or remote. 12 * 13 * These counters are not meant to be human-readable, but are meant to be 14 * integrated into system monitoring tools such as "sar" and "iostat". As 15 * such, the counters are sampled by the tools over time, and are never 16 * zeroed after a file system is mounted. Moving averages can be computed 17 * by the tools by taking the difference between two instantaneous samples 18 * and dividing that by the time between the samples. 19 * 20 * The counters are maintained in a single array per RPC client, indexed 21 * by procedure number. There is no need to maintain separate counter 22 * arrays per-CPU because these counters are always modified behind locks. 23 */ 24 25#ifndef _LINUX_SUNRPC_METRICS_H 26#define _LINUX_SUNRPC_METRICS_H 27 28#include <linux/seq_file.h> 29 30#define RPC_IOSTATS_VERS "1.0" 31 32struct rpc_iostats { 33 /* 34 * These counters give an idea about how many request 35 * transmissions are required, on average, to complete that 36 * particular procedure. Some procedures may require more 37 * than one transmission because the server is unresponsive, 38 * the client is retransmitting too aggressively, or the 39 * requests are large and the network is congested. 40 */ 41 unsigned long om_ops, /* count of operations */ 42 om_ntrans, /* count of RPC transmissions */ 43 om_timeouts; /* count of major timeouts */ 44 45 /* 46 * These count how many bytes are sent and received for a 47 * given RPC procedure type. This indicates how much load a 48 * particular procedure is putting on the network. These 49 * counts include the RPC and ULP headers, and the request 50 * payload. 51 */ 52 unsigned long long om_bytes_sent, /* count of bytes out */ 53 om_bytes_recv; /* count of bytes in */ 54 55 /* 56 * The length of time an RPC request waits in queue before 57 * transmission, the network + server latency of the request, 58 * and the total time the request spent from init to release 59 * are measured. 60 */ 61 unsigned long long om_queue, /* jiffies queued for xmit */ 62 om_rtt, /* jiffies for RPC RTT */ 63 om_execute; /* jiffies for RPC execution */ 64} ____cacheline_aligned; 65 66struct rpc_task; 67struct rpc_clnt; 68 69/* 70 * EXPORTed functions for managing rpc_iostats structures 71 */ 72 73#ifdef CONFIG_PROC_FS 74 75struct rpc_iostats * rpc_alloc_iostats(struct rpc_clnt *); 76void rpc_count_iostats(struct rpc_task *); 77void rpc_print_iostats(struct seq_file *, struct rpc_clnt *); 78void rpc_free_iostats(struct rpc_iostats *); 79 80#else /* CONFIG_PROC_FS */ 81 82static inline struct rpc_iostats *rpc_alloc_iostats(struct rpc_clnt *clnt) { return NULL; } 83static inline void rpc_count_iostats(struct rpc_task *task) {} 84static inline void rpc_print_iostats(struct seq_file *seq, struct rpc_clnt *clnt) {} 85static inline void rpc_free_iostats(struct rpc_iostats *stats) {} 86 87#endif /* CONFIG_PROC_FS */ 88 89#endif /* _LINUX_SUNRPC_METRICS_H */ 90