diff --git a/media/codec2/sfplugin/CCodec.cpp b/media/codec2/sfplugin/CCodec.cpp
index aa7189c..895be1a 100644
--- a/media/codec2/sfplugin/CCodec.cpp
+++ b/media/codec2/sfplugin/CCodec.cpp
@@ -374,7 +374,11 @@
 
         // consumer usage is queried earlier.
 
-        ALOGD("ISConfig%s", status.str().c_str());
+        if (status.str().empty()) {
+            ALOGD("ISConfig not changed");
+        } else {
+            ALOGD("ISConfig%s", status.str().c_str());
+        }
         return err;
     }
 
diff --git a/media/codec2/sfplugin/CCodecConfig.cpp b/media/codec2/sfplugin/CCodecConfig.cpp
index 1cfdc19..104b10b 100644
--- a/media/codec2/sfplugin/CCodecConfig.cpp
+++ b/media/codec2/sfplugin/CCodecConfig.cpp
@@ -235,7 +235,10 @@
     const std::vector<ConfigMapper> &getConfigMappersForSdkKey(std::string key) const {
         auto it = mConfigMappers.find(key);
         if (it == mConfigMappers.end()) {
-            ALOGD("no c2 equivalents for %s", key.c_str());
+            if (mComplained.count(key) == 0) {
+                ALOGD("no c2 equivalents for %s", key.c_str());
+                mComplained.insert(key);
+            }
             return NO_MAPPERS;
         }
         ALOGV("found %zu eqs for %s", it->second.size(), key.c_str());
@@ -304,6 +307,7 @@
 
 private:
     std::map<SdkKey, std::vector<ConfigMapper>> mConfigMappers;
+    mutable std::set<std::string> mComplained;
 };
 
 const std::vector<ConfigMapper> StandardParams::NO_MAPPERS;
@@ -1033,7 +1037,25 @@
     }
 
     ReflectedParamUpdater::Dict reflected = mParamUpdater->getParams(paramPointers);
-    ALOGD("c2 config is %s", reflected.debugString().c_str());
+    std::string config = reflected.debugString();
+    std::set<std::string> configLines;
+    std::string diff;
+    for (size_t start = 0; start != std::string::npos; ) {
+        size_t end = config.find('\n', start);
+        size_t count = (end == std::string::npos)
+                ? std::string::npos
+                : end - start + 1;
+        std::string line = config.substr(start, count);
+        configLines.insert(line);
+        if (mLastConfig.count(line) == 0) {
+            diff.append(line);
+        }
+        start = (end == std::string::npos) ? std::string::npos : end + 1;
+    }
+    if (!diff.empty()) {
+        ALOGD("c2 config diff is %s", diff.c_str());
+    }
+    mLastConfig.swap(configLines);
 
     bool changed = false;
     if (domain & mInputDomain) {
diff --git a/media/codec2/sfplugin/CCodecConfig.h b/media/codec2/sfplugin/CCodecConfig.h
index 3bafe3f..a61c8b7 100644
--- a/media/codec2/sfplugin/CCodecConfig.h
+++ b/media/codec2/sfplugin/CCodecConfig.h
@@ -134,6 +134,8 @@
     /// For now support a validation function.
     std::map<C2Param::Index, LocalParamValidator> mLocalParams;
 
+    std::set<std::string> mLastConfig;
+
     CCodecConfig();
 
     /// initializes the members required to manage the format: descriptors, reflector,