Merge pull request #1998 from ktsaou/master

[netdata.git] / src / adaptive_resortable_list.c

diff --git a/src/adaptive_resortable_list.c b/src/adaptive_resortable_list.c
index 032d553c3a7c6e61de663f5eb5af798ebf4f3d67..f74c53eae5e192845ae57ed7975eb3ee9d8d5034 100644 (file)
--- a/src/adaptive_resortable_list.c
+++ b/src/adaptive_resortable_list.c
@@ -12,9 +12,11 @@ static inline void arl_callback_str2ull(const char *name, uint32_t hash, const c
 }
 
 // create a new ARL
-ARL_BASE *arl_create(void (*processor)(const char *, uint32_t, const char *, void *), size_t rechecks) {
+ARL_BASE *arl_create(const char *name, void (*processor)(const char *, uint32_t, const char *, void *), size_t rechecks) {
     ARL_BASE *base = callocz(1, sizeof(ARL_BASE));
 
+    base->name = strdupz(name);
+
     if(!processor)
         base->processor = arl_callback_str2ull;
     else
@@ -40,6 +42,8 @@ void arl_free(ARL_BASE *arl_base) {
         freez(e);
     }
 
+    freez(arl_base->name);
+
 #ifdef NETDATA_INTERNAL_CHECKS
     memset(arl_base, 0, sizeof(ARL_BASE));
 #endif
@@ -48,29 +52,46 @@ void arl_free(ARL_BASE *arl_base) {
 }
 
 void arl_begin(ARL_BASE *base) {
-    ARL_ENTRY *e;
 
-    /*
-    info("iteration %zu, expected %zu, wanted %zu, allocated %zu, fred %zu, relinkings %zu, found %zu, added %zu, fast %zu, slow %zu"
-         , base->iteration
-         , base->expected
-         , base->wanted
-         , base->allocated
-         , base->fred
-         , base->relinkings
-         , base->found
-         , base->added
-         , base->fast
-         , base->slow
-    );
-    for(e = base->head; e ; e = e->next) fprintf(stderr, "%s ", e->name);
-    fprintf(stderr, "\n");
-     */
+#ifdef NETDATA_INTERNAL_CHECKS
+    if(likely(base->iteration > 10)) {
+        // do these checks after the ARL has been sorted
+
+        if(unlikely(base->relinkings > (base->expected + base->allocated)))
+            info("ARL '%s' has %zu relinkings with %zu expected and %zu allocated entries. Is the source changing so fast?"
+                 , base->name, base->relinkings, base->expected, base->allocated);
+
+        if(unlikely(base->slow > base->fast))
+            info("ARL '%s' has %zu fast searches and %zu slow searches. Is the source really changing so fast?"
+                 , base->name, base->fast, base->slow);
+
+        /*
+        if(unlikely(base->iteration % 60 == 0)) {
+            info("ARL '%s' statistics: iteration %zu, expected %zu, wanted %zu, allocated %zu, fred %zu, relinkings %zu, found %zu, added %zu, fast %zu, slow %zu"
+                 , base->name
+                 , base->iteration
+                 , base->expected
+                 , base->wanted
+                 , base->allocated
+                 , base->fred
+                 , base->relinkings
+                 , base->found
+                 , base->added
+                 , base->fast
+                 , base->slow
+            );
+            // for(e = base->head; e; e = e->next) fprintf(stderr, "%s ", e->name);
+            // fprintf(stderr, "\n");
+        }
+        */
+    }
+#endif
 
     if(unlikely(base->added || base->iteration % base->rechecks) == 1) {
         base->added = 0;
         base->wanted = 0;
-        for(e = base->head; e ; e = e->next) {
+        ARL_ENTRY *e = base->head;
+        while(e) {
             if(e->flags & ARL_ENTRY_FLAG_FOUND) {
 
                 // remove the found flag
@@ -79,25 +100,48 @@ void arl_begin(ARL_BASE *base) {
                 // count it in wanted
                 if(e->flags & ARL_ENTRY_FLAG_EXPECTED)
                     base->wanted++;
+
             }
-            else if(e->flags & ARL_ENTRY_FLAG_DYNAMIC) {
+            else if(e->flags & ARL_ENTRY_FLAG_DYNAMIC && !(base->head == e && !e->next)) { // not last entry
                 // we can remove this entry
                 // it is not found, and it was created because
                 // it was found in the source file
+
+                // remember the next one
+                ARL_ENTRY *t = e->next;
+
+                // remove it from the list
                 if(e->next) e->next->prev = e->prev;
                 if(e->prev) e->prev->next = e->next;
                 if(base->head == e) base->head = e->next;
+
+                // free it
                 freez(e->name);
                 freez(e);
 
+                // count it
                 base->fred++;
+
+                // continue
+                e = t;
+                continue;
             }
+
+            e = e->next;
         }
     }
 
+    if(unlikely(!base->head)) {
+        // hm... no nodes at all in the list #1700
+        // add a fake one to prevent a crash
+        // this is better than checking for the existence of nodes all the time
+        arl_expect(base, "a-really-not-existing-source-keyword", NULL);
+    }
+
     base->iteration++;
     base->next_keyword = base->head;
     base->found = 0;
+
 }
 
 // register an expected keyword to the ARL
@@ -134,12 +178,13 @@ int arl_find_or_create_and_relink(ARL_BASE *base, const char *s, const char *val
             break;
 
 #ifdef NETDATA_INTERNAL_CHECKS
-    if(unlikely(e == base->next_keyword))
+    if(unlikely(base->next_keyword && e == base->next_keyword))
         fatal("Internal Error: e == base->last");
 #endif
 
     if(e) {
         // found it in the keywords
+
         base->relinkings++;
 
         // run the processor for it
@@ -169,6 +214,11 @@ int arl_find_or_create_and_relink(ARL_BASE *base, const char *s, const char *val
         base->added++;
     }
 
+#ifdef NETDATA_INTERNAL_CHECKS
+    if(unlikely(base->iteration % 60 == 0 && e->flags & ARL_ENTRY_FLAG_FOUND))
+        info("ARL '%s': entry '%s' is already found. Did you forget to call arl_begin()?", base->name, s);
+#endif
+
     e->flags |= ARL_ENTRY_FLAG_FOUND;
 
     // link it here
@@ -183,9 +233,14 @@ int arl_find_or_create_and_relink(ARL_BASE *base, const char *s, const char *val
         if(base->head == base->next_keyword)
             base->head = e;
     }
-    else
+    else {
         e->prev = NULL;
 
+        if(!base->head)
+            base->head = e;
+    }
+
+    // prepare the next iteration
     base->next_keyword = e->next;
     if(unlikely(!base->next_keyword))
         base->next_keyword = base->head;