From af2fda0724adbce9a8ef6586ec1028d4966864a2 Mon Sep 17 00:00:00 2001
From: Dmitry Kurochkin <dmitry.kurochkin@measurement-factory.com>
Date: Mon, 18 Apr 2011 15:53:16 +0400
Subject: [PATCH] Warn if MemStore cannot support the configured maximum
 disk-cache entry size.

---
 src/MemStore.cc      | 20 +++++++++++++++++++-
 src/MemStore.h       |  1 +
 src/Store.h          |  3 +++
 src/StoreHashIndex.h |  2 ++
 src/SwapDir.h        |  4 ++++
 src/store_dir.cc     | 19 +++++++++++++++++++
 6 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/src/MemStore.cc b/src/MemStore.cc
index 517a495143..fe6680036b 100644
--- a/src/MemStore.cc
+++ b/src/MemStore.cc
@@ -44,6 +44,19 @@ MemStore::init() {
     if (entryLimit <= 0)
         return; // no memory cache configured or a misconfiguration
 
+    if (IamWorkerProcess()) { // XXX: coordinator should not create MemStore
+        const int64_t max_size = Store::Root().maxObjectSize();
+        if (max_size == -1) {
+            debugs(20, DBG_IMPORTANT, "WARNING: disk-cache maximum object size "
+                   "is unlimited but mem-cache maximum object size is " <<
+                   Ipc::Mem::PageSize());
+        } else if (max_size > maxObjectSize()) {
+            debugs(20, DBG_IMPORTANT, "WARNING: disk-cache maximum object size "
+                   "is too large for mem-cache: " <<
+                   Store::Root().maxObjectSize() << " > " << maxObjectSize());
+        }
+    }
+
     map = new MemStoreMap(ShmLabel);
     map->cleaner = this;
 }
@@ -100,6 +113,12 @@ MemStore::currentCount() const
     return map ? map->entryCount() : 0;
 }
 
+int64_t
+MemStore::maxObjectSize() const
+{
+    return Ipc::Mem::PageSize();
+}
+
 void
 MemStore::updateSize(int64_t eSize, int sign)
 {
@@ -332,7 +351,6 @@ MemStore::EntryLimit()
     if (!Config.memMaxSize)
         return 0; // no memory cache configured
 
-    // TODO: warn if we cannot support the configured maximum entry size
     const int64_t entrySize = Ipc::Mem::PageSize(); // for now
     const int64_t entryLimit = Config.memMaxSize / entrySize;
     // TODO: warn if we cannot cache at least one item (misconfiguration)
diff --git a/src/MemStore.h b/src/MemStore.h
index b628e25898..ca5e60cea3 100644
--- a/src/MemStore.h
+++ b/src/MemStore.h
@@ -27,6 +27,7 @@ public:
     virtual uint64_t minSize() const;
     virtual uint64_t currentSize() const;
     virtual uint64_t currentCount() const;
+    virtual int64_t maxObjectSize() const;
     virtual void stat(StoreEntry &) const;
     virtual StoreSearch *search(String const url, HttpRequest *);
     virtual void reference(StoreEntry &);
diff --git a/src/Store.h b/src/Store.h
index d12d1ffccf..4b731be01c 100644
--- a/src/Store.h
+++ b/src/Store.h
@@ -306,6 +306,9 @@ public:
     /** the total number of objects stored */
     virtual uint64_t currentCount() const = 0;
 
+    /** the maximum object size that can be stored, -1 if unlimited */
+    virtual int64_t maxObjectSize() const = 0;
+
     /**
      * Output stats to the provided store entry.
      \todo make these calls asynchronous
diff --git a/src/StoreHashIndex.h b/src/StoreHashIndex.h
index 8ed0c00991..b3badea2ad 100644
--- a/src/StoreHashIndex.h
+++ b/src/StoreHashIndex.h
@@ -71,6 +71,8 @@ public:
 
     virtual uint64_t currentCount() const;
 
+    virtual int64_t maxObjectSize() const;
+
     virtual void stat(StoreEntry&) const;
 
     virtual void reference(StoreEntry&);
diff --git a/src/SwapDir.h b/src/SwapDir.h
index df0648f8a5..53dde7126c 100644
--- a/src/SwapDir.h
+++ b/src/SwapDir.h
@@ -73,6 +73,8 @@ public:
 
     virtual uint64_t currentCount() const;
 
+    virtual int64_t maxObjectSize() const;
+
     virtual void stat(StoreEntry &) const;
 
     virtual void sync();	/* Sync the store prior to shutdown */
@@ -146,6 +148,8 @@ public:
 
     virtual uint64_t currentCount() const { return n_disk_objects; }
 
+    virtual int64_t maxObjectSize() const { return max_objsize; }
+
     virtual void stat (StoreEntry &anEntry) const;
     virtual StoreSearch *search(String const url, HttpRequest *) = 0;
 
diff --git a/src/store_dir.cc b/src/store_dir.cc
index 4d64c018e5..922bb7d786 100644
--- a/src/store_dir.cc
+++ b/src/store_dir.cc
@@ -389,6 +389,12 @@ StoreController::currentCount() const
     return swapDir->currentCount();
 }
 
+int64_t
+StoreController::maxObjectSize() const
+{
+    return swapDir->maxObjectSize();
+}
+
 void
 SwapDir::diskFull()
 {
@@ -958,6 +964,19 @@ StoreHashIndex::currentCount() const
     return result;
 }
 
+int64_t
+StoreHashIndex::maxObjectSize() const
+{
+    int64_t result = -1;
+
+    for (int i = 0; i < Config.cacheSwap.n_configured; i++) {
+        if (dir(i).active() && store(i)->maxObjectSize() > result)
+            result = store(i)->maxObjectSize();
+    }
+
+    return result;
+}
+
 void
 StoreHashIndex::stat(StoreEntry & output) const
 {
-- 
2.47.2