3 files changed, 38 insertions, 8 deletions

diff --git a/src/cache.h b/src/cache.h
index 036ceb4..4ae1aa8 100644
--- a/src/cache.h
+++ b/src/cache.h
@@ -143,6 +143,7 @@ namespace Bu
                 {
                         obtype *pData;
                         int iRefs;
+                        time_t tLastSync;
                 } CacheEntry;
 
                 typedef Bu::Hash<keytype, CacheEntry> CidHash;
@@ -184,7 +185,7 @@ namespace Bu
                 Ptr insert( obtype *pData )
                 {
                         TRACE( pData );
-                        CacheEntry e = {pData, 0};
+                        CacheEntry e = {pData, 0, 0};
                         keytype k = pStore->create( pData );
                         hEnt.insert( k, e );
 
@@ -205,7 +206,7 @@ namespace Bu
                                 return Ptr( this, hEnt.get( cId ).pData, cId );
                         }
                         catch( Bu::HashException &e ) {
-                                CacheEntry e = {pStore->load( cId ), 0};
+                                CacheEntry e = {pStore->load( cId ), 0, time( NULL )};
                                 pCalc->onLoad( e.pData, cId );
                                 hEnt.insert( cId, e );
                                 return Ptr( this, e.pData, cId );
@@ -285,11 +286,19 @@ namespace Bu
                         {
                                 if( i.getValue().iRefs == 0 )
                                 {
-                                        pStore->sync(
-                                                i.getValue().pData,
-                                                i.getKey()
-                                                );
-                                        iSynced++;
+                                        if( pCalc->shouldSync(
+                                                        i.getValue().pData,
+                                                        i.getKey(),
+                                                        i.getValue().tLastSync
+                                                        ) )
+                                        {
+                                                pStore->sync(
+                                                        i.getValue().pData,
+                                                        i.getKey()
+                                                        );
+                                                iSynced++;
+                                                i.getValue().tLastSync = time( NULL );
+                                        }
                                 }
                         }
                         if( iSynced > 0 )
@@ -319,7 +328,7 @@ namespace Bu
                                 return hEnt.get( cId ).pData;
                         }
                         catch( Bu::HashException &e ) {
-                                CacheEntry e = {pStore->load( cId ), 0};
+                                CacheEntry e = {pStore->load( cId ), 0, time( NULL )};
                                 pCalc->onLoad( e.pData, cId );
                                 hEnt.insert( cId, e );
                                 return e.pData;
diff --git a/src/cachecalc.h b/src/cachecalc.h
index dd9712f..7fdb16e 100644
--- a/src/cachecalc.h
+++ b/src/cachecalc.h
@@ -3,6 +3,8 @@
 
 #include "bu/trace.h"
 
+#include <time.h>
+
 namespace Bu
 {
         template<class obtype, class keytype> class Cache;
@@ -27,6 +29,8 @@ namespace Bu
 
                 virtual void onLoad( obtype *pSrc, const keytype &key )=0;
                 virtual void onUnload( obtype *pSrc, const keytype &key )=0;
+                virtual bool shouldSync( obtype *pSrc, const keytype &key,
+                        time_t tLastSync )=0;
                 virtual void onTick() { };
 
         protected:
diff --git a/src/tests/cache.cpp b/src/tests/cache.cpp
index 323edda..8d95a9d 100644
--- a/src/tests/cache.cpp
+++ b/src/tests/cache.cpp
@@ -96,6 +96,19 @@ public:
                 f.write( s );
         }
 
+        virtual void sync( Bob *, const long & )
+        {
+        }
+
+        virtual void sync()
+        {
+        }
+
+        virtual bool has( const long & )
+        {
+                return true;
+        }
+
         virtual Bob *load( const long &key )
         {
                 TRACE( key );
@@ -156,6 +169,10 @@ public:
         {
         }
 
+        virtual bool shouldSync( Bob *, const long &, time_t )
+        {
+        }
+
 private:
 
 };