refine the cpu stat, use fgets and sscanf.

@@ -194,7 +194,6 @@ SrsProcSystemStat::SrsProcSystemStat()
     sample_time = 0;
     percent = 0;
     total_delta = 0;
-    memset(label, 0, sizeof(label));
     user = 0;
     nice = 0;
     sys = 0;
@@ -229,21 +228,29 @@ bool get_proc_system_stat(SrsProcSystemStat& r)
         return false;
     }
     
-    for (;;) {
-        int ret = fscanf(f, "%4s %lu %lu %lu %lu %lu "
-            "%lu %lu %lu %lu\n", 
-            r.label, &r.user, &r.nice, &r.sys, &r.idle, &r.iowait,
-            &r.irq, &r.softirq, &r.steal, &r.guest);
-        r.ok = false;
-        
-        if (ret == EOF) {
-            break;
+    r.ok = false;
+    
+    static char buf[1024];
+    while (fgets(buf, sizeof(buf), f)) {
+        if (strncmp(buf, "cpu ", 4) != 0) {
+            continue;
         }
         
-        if (strcmp("cpu", r.label) == 0) {
-            r.ok = true;
-            break;
-        }
+        int ret = sscanf(buf, "cpu %llu %llu %llu %llu %llu "
+            "%llu %llu %llu %llu\n", 
+            &r.user, &r.nice, &r.sys, &r.idle, &r.iowait,
+            &r.irq, &r.softirq, &r.steal, &r.guest);
+        srs_assert(ret == 9);
+
+        // matched ok.
+        r.ok = true;
+        
+        // @see: http://tester-higkoo.googlecode.com/svn-history/r14/trunk/Tools/iostat/iostat.c
+        // add the interrupts to sys.
+        // TODO: FIXME: check out it.
+        r.sys += r.irq + r.softirq;
+
+        break;
     }
     
     fclose(f);
@@ -358,6 +365,14 @@ SrsDiskStat::SrsDiskStat()
     
     pgpgin = 0;
     pgpgout = 0;
+    
+    rd_ios = rd_merges = 0;
+    rd_sectors = 0;
+    rd_ticks = 0;
+    
+    wr_ios = wr_merges = 0;
+    wr_sectors = 0;
+    wr_ticks = nb_current = ticks = aveq = 0;
 }
 
 static SrsDiskStat _srs_disk_stat;
@@ -403,6 +418,64 @@ bool srs_get_disk_vmstat_stat(SrsDiskStat& r)
 
 bool srs_get_disk_diskstats_stat(SrsDiskStat& r)
 {
+    // %4d %4d %31s %u
+    // 
+    FILE* f = fopen("/proc/diskstats", "r");
+    if (f == NULL) {
+        srs_warn("open vmstat failed, ignore");
+        return false;
+    }
+    
+    r.ok = false;
+    r.sample_time = srs_get_system_time_ms();
+    
+    static char buf[1024];
+    
+    while (fgets(buf, sizeof(buf), f)) {
+        unsigned int major = 0;
+        unsigned int minor = 0;
+        static char name[32];
+        unsigned int rd_ios = 0;
+        unsigned int rd_merges = 0;
+        unsigned long long rd_sectors = 0;
+        unsigned int rd_ticks = 0;
+        unsigned int wr_ios = 0;
+        unsigned int wr_merges = 0;
+        unsigned long long wr_sectors = 0;
+        unsigned int wr_ticks = 0;
+        unsigned int nb_current = 0;
+        unsigned int ticks = 0;
+        unsigned int aveq = 0;
+        memset(name, sizeof(name), 0);
+        int ret = sscanf(buf, 
+            "%4d %4d %31s %u %u %llu %u %u %u %llu %u %u %u %u", 
+            &major, &minor, name, &rd_ios, &rd_merges,
+            &rd_sectors, &rd_ticks, &wr_ios, &wr_merges,
+            &wr_sectors, &wr_ticks, &nb_current, &ticks, &aveq);
+        
+        if (ret == EOF) {
+            break;
+        }
+        
+        if (strcmp("sda", name) == 0) {
+            r.rd_ios += rd_ios;
+            r.rd_merges += rd_merges;
+            r.rd_sectors += rd_sectors;
+            r.rd_ticks += rd_ticks;
+            r.wr_ios += wr_ios;
+            r.wr_merges += wr_merges;
+            r.wr_sectors += wr_sectors;
+            r.wr_ticks += wr_ticks;
+            r.nb_current += nb_current;
+            r.ticks += ticks;
+            r.aveq += aveq;
+        }
+    }
+    
+    fclose(f);
+    
+    r.ok = true;
+    
     return true;
 }
 

@@ -273,9 +273,6 @@ public:
     //          previous cpu total = this->total() - total_delta
     int64_t total_delta;
     
-    // always be cpu
-    char label[32];
-    
 // data of /proc/stat
 public:
     // The amount of time, measured in units  of  USER_HZ  
@@ -283,32 +280,32 @@ public:
     // sysconf(_SC_CLK_TCK)  to  obtain  the  right value)
     //
     // the system spent in user mode, 
-    unsigned long user;
+    unsigned long long user;
     // user mode with low priority (nice), 
-    unsigned long nice;
+    unsigned long long nice;
     // system mode, 
-    unsigned long sys;
+    unsigned long long sys;
     // and the idle task, respectively.
-    unsigned long idle;
+    unsigned long long idle;
 
     // In  Linux 2.6 this line includes three additional columns:
     //
     // iowait - time waiting for I/O to complete (since 2.5.41);
-    unsigned long iowait;
+    unsigned long long iowait;
     // irq - time servicing interrupts (since 2.6.0-test4); 
-    unsigned long irq;
+    unsigned long long irq;
     // softirq  -  time  servicing  softirqs  (since 2.6.0-test4).
-    unsigned long softirq;
+    unsigned long long softirq;
     
     // Since  Linux 2.6.11, there is an eighth column,
     // steal - stolen time, which is the time spent in other oper-
     // ating systems when running in a virtualized environment
-    unsigned long steal;
+    unsigned long long steal;
     
     // Since Linux 2.6.24, there is a ninth column, 
     // guest, which is the time spent running a virtual CPU for guest
     // operating systems under the control of the Linux kernel.
-    unsigned long guest;
+    unsigned long long guest;
 
 public:
     SrsProcSystemStat();
@@ -350,46 +347,56 @@ public:
     unsigned long pgpgout;
     
     // @see: https://www.kernel.org/doc/Documentation/iostats.txt
+    // @see: http://tester-higkoo.googlecode.com/svn-history/r14/trunk/Tools/iostat/iostat.c
     // @see: cat /proc/diskstats
     //
     // Number of issued reads. 
     // This is the total number of reads completed successfully.
-    unsigned long long nb_read;
+    // Read I/O operations
+    unsigned int rd_ios;
     // Number of reads merged
-    unsigned long long nb_mread;
+    // Reads merged
+    unsigned int rd_merges;
     // Number of sectors read. 
     // This is the total number of sectors read successfully.
-    unsigned long long nb_sread;
+    // Sectors read
+    unsigned long long rd_sectors;
     // Number of milliseconds spent reading. 
     // This is the total number of milliseconds spent by all reads 
     // (as measured from __make_request() to end_that_request_last()).
-    unsigned long long ms_read;
+    // Time in queue + service for read
+    unsigned int rd_ticks;
     //
     // Number of writes completed. 
     // This is the total number of writes completed successfully
-    unsigned long long nb_write;
+    // Write I/O operations
+    unsigned int wr_ios;
     // Number of writes merged Reads and writes which are adjacent 
     // to each other may be merged for efficiency. Thus two 4K 
     // reads may become one 8K read before it is ultimately 
     // handed to the disk, and so it will be counted (and queued) 
     // as only one I/O. This field lets you know how often this was done.
-    unsigned long long nb_mwrite;
+    // Writes merged
+    unsigned int wr_merges;
     // Number of sectors written. 
     // This is the total number of sectors written successfully.
-    unsigned long long nb_swrite;
+    // Sectors written
+    unsigned long long wr_sectors;
     // Number of milliseconds spent writing . 
     // This is the total number of milliseconds spent by all writes 
     // (as measured from __make_request() to end_that_request_last()).
-    unsigned long long ms_write;
+    // Time in queue + service for write
+    unsigned int wr_ticks;
     //
     // Number of I/Os currently in progress. 
     // The only field that should go to zero. 
     // Incremented as requests are given to appropriate request_queue_t 
     // and decremented as they finish.
-    unsigned long long nb_current;
+    unsigned int nb_current;
     // Number of milliseconds spent doing I/Os. 
     // This field is increased so long as field 9 is nonzero.
-    unsigned long long ms_total;
+    // Time of requests in queue
+    unsigned int ticks;
     // Number of milliseconds spent doing I/Os. 
     // This field is incremented at each I/O start, I/O completion, 
     // I/O merge, or read of these stats by the number of I/Os in 
@@ -397,8 +404,8 @@ public:
     // doing I/O since the last update of this field. This can 
     // provide an easy measure of both I/O completion time and 
     // the backlog that may be accumulating.
-    // weighting total.
-    unsigned long long ms_wtotal;
+    // Average queue length
+    unsigned int aveq;
 
 public:
     SrsDiskStat();