diff --git a/amalgamation/xgboost-all0.cc b/amalgamation/xgboost-all0.cc
index 645695dec..7cc36c16b 100644
--- a/amalgamation/xgboost-all0.cc
+++ b/amalgamation/xgboost-all0.cc
@@ -30,6 +30,7 @@
 #include "../src/data/data.cc"
 #include "../src/data/simple_csr_source.cc"
 #include "../src/data/simple_dmatrix.cc"
+#include "../src/data/sparse_page_raw_format.cc"
 
 #if DMLC_ENABLE_STD_THREAD
 #include "../src/data/sparse_page_source.cc"
diff --git a/src/data/data.cc b/src/data/data.cc
index d73c1e8bb..30da58e8e 100644
--- a/src/data/data.cc
+++ b/src/data/data.cc
@@ -4,6 +4,7 @@
  */
 #include <xgboost/data.h>
 #include <xgboost/logging.h>
+#include <dmlc/registry.h>
 #include <cstring>
 #include "./sparse_batch_page.h"
 #include "./simple_dmatrix.h"
@@ -15,6 +16,10 @@
 #include "./sparse_page_dmatrix.h"
 #endif
 
+namespace dmlc {
+DMLC_REGISTRY_ENABLE(::xgboost::data::SparsePageFormatReg);
+}  // namespace dmlc
+
 namespace xgboost {
 // implementation of inline functions
 void MetaInfo::Clear() {
@@ -231,3 +236,24 @@ DMatrix* DMatrix::Create(std::unique_ptr<DataSource>&& source,
   }
 }
 }  // namespace xgboost
+
+namespace xgboost {
+namespace data {
+SparsePage::Format* SparsePage::Format::Create(const std::string& name) {
+  auto *e = ::dmlc::Registry< ::xgboost::data::SparsePageFormatReg>::Get()->Find(name);
+  if (e == nullptr) {
+    LOG(FATAL) << "Unknown format type " << name;
+  }
+  return (e->body)();
+}
+
+std::string SparsePage::Format::DecideFormat(const std::string& cache_prefix) {
+  size_t pos = cache_prefix.rfind(".fmt-");
+  if (pos != std::string::npos) {
+    return cache_prefix.substr(pos + 5, cache_prefix.length());
+  } else {
+    return "raw";
+  }
+}
+}  // namespace data
+}  // namespace xgboost
diff --git a/src/data/sparse_batch_page.h b/src/data/sparse_batch_page.h
index 145495e29..78534bfd6 100644
--- a/src/data/sparse_batch_page.h
+++ b/src/data/sparse_batch_page.h
@@ -14,6 +14,7 @@
 #include <vector>
 #include <algorithm>
 #include <cstring>
+#include <string>
 
 namespace xgboost {
 namespace data {
@@ -22,6 +23,9 @@ namespace data {
  */
 class SparsePage {
  public:
+  /*! \brief Format of the sparse page. */
+  class Format;
+
   /*! \brief offset of the segments */
   std::vector<size_t> offset;
   /*! \brief the data of the segments */
@@ -35,87 +39,6 @@ class SparsePage {
   inline size_t Size() const {
     return offset.size() - 1;
   }
-  /*!
-   * \brief load only the segments we are interested in
-   * \param fi the input stream of the file
-   * \param sorted_index_set sorted index of segments we are interested in
-   * \return true of the loading as successful, false if end of file was reached
-   */
-  inline bool Load(dmlc::SeekStream *fi,
-                   const std::vector<bst_uint> &sorted_index_set) {
-    if (!fi->Read(&disk_offset_)) return false;
-    // setup the offset
-    offset.clear(); offset.push_back(0);
-    for (size_t i = 0; i < sorted_index_set.size(); ++i) {
-      bst_uint fid = sorted_index_set[i];
-      CHECK_LT(fid + 1, disk_offset_.size());
-      size_t size = disk_offset_[fid + 1] - disk_offset_[fid];
-      offset.push_back(offset.back() + size);
-    }
-    data.resize(offset.back());
-    // read in the data
-    size_t begin = fi->Tell();
-    size_t curr_offset = 0;
-    for (size_t i = 0; i < sorted_index_set.size();) {
-      bst_uint fid = sorted_index_set[i];
-      if (disk_offset_[fid] != curr_offset) {
-        CHECK_GT(disk_offset_[fid], curr_offset);
-        fi->Seek(begin + disk_offset_[fid] * sizeof(SparseBatch::Entry));
-        curr_offset = disk_offset_[fid];
-      }
-      size_t j, size_to_read = 0;
-      for (j = i; j < sorted_index_set.size(); ++j) {
-        if (disk_offset_[sorted_index_set[j]] == disk_offset_[fid] + size_to_read) {
-          size_to_read += offset[j + 1] - offset[j];
-        } else {
-          break;
-        }
-      }
-
-      if (size_to_read != 0) {
-        CHECK_EQ(fi->Read(dmlc::BeginPtr(data) + offset[i],
-                          size_to_read * sizeof(SparseBatch::Entry)),
-                 size_to_read * sizeof(SparseBatch::Entry))
-            << "Invalid SparsePage file";
-        curr_offset += size_to_read;
-      }
-      i = j;
-    }
-    // seek to end of record
-    if (curr_offset != disk_offset_.back()) {
-      fi->Seek(begin + disk_offset_.back() * sizeof(SparseBatch::Entry));
-    }
-    return true;
-  }
-  /*!
-   * \brief load all the segments
-   * \param fi the input stream of the file
-   * \return true of the loading as successful, false if end of file was reached
-   */
-  inline bool Load(dmlc::Stream *fi) {
-    if (!fi->Read(&offset)) return false;
-    CHECK_NE(offset.size(), 0) << "Invalid SparsePage file";
-    data.resize(offset.back());
-    if (data.size() != 0) {
-      CHECK_EQ(fi->Read(dmlc::BeginPtr(data), data.size() * sizeof(SparseBatch::Entry)),
-               data.size() * sizeof(SparseBatch::Entry))
-          << "Invalid SparsePage file";
-    }
-    return true;
-  }
-  /*!
-   * \brief save the data to fo, when a page was written
-   *    to disk it must contain all the elements in the
-   * \param fo output stream
-   */
-  inline void Save(dmlc::Stream *fo) const {
-    CHECK(offset.size() != 0 && offset[0] == 0);
-    CHECK_EQ(offset.back(), data.size());
-    fo->Write(offset);
-    if (data.size() != 0) {
-      fo->Write(dmlc::BeginPtr(data), data.size() * sizeof(SparseBatch::Entry));
-    }
-  }
   /*! \return estimation of memory cost of this page */
   inline size_t MemCostBytes(void) const {
     return offset.size() * sizeof(size_t) + data.size() * sizeof(SparseBatch::Entry);
@@ -126,28 +49,7 @@ class SparsePage {
     offset.push_back(0);
     data.clear();
   }
-  /*!
-   * \brief load all the segments and add it to existing batch
-   * \param fi the input stream of the file
-   * \return true of the loading as successful, false if end of file was reached
-   */
-  inline bool PushLoad(dmlc::Stream *fi) {
-    if (!fi->Read(&disk_offset_)) return false;
-    data.resize(offset.back() + disk_offset_.back());
-    if (disk_offset_.back() != 0) {
-      CHECK_EQ(fi->Read(dmlc::BeginPtr(data) + offset.back(),
-                        disk_offset_.back() * sizeof(SparseBatch::Entry)),
-               disk_offset_.back() * sizeof(SparseBatch::Entry))
-          << "Invalid SparsePage file";
-    }
-    size_t top = offset.back();
-    size_t begin = offset.size();
-    offset.resize(offset.size() + disk_offset_.size());
-    for (size_t i = 0; i < disk_offset_.size(); ++i) {
-      offset[i + begin] = top + disk_offset_[i];
-    }
-    return true;
-  }
+
   /*!
    * \brief Push row batch into the page
    * \param batch the row batch
@@ -223,11 +125,72 @@ class SparsePage {
     out.size = offset.size() - 1;
     return out;
   }
-
- private:
-  /*! \brief external memory column offset */
-  std::vector<size_t> disk_offset_;
 };
+
+/*!
+ * \brief Format specification of SparsePage.
+ */
+class SparsePage::Format {
+ public:
+  /*! \brief virtual destructor */
+  virtual ~Format() {}
+  /*!
+   * \brief Load all the segments into page, advance fi to end of the block.
+   * \param page The data to read page into.
+   * \param fi the input stream of the file
+   * \return true of the loading as successful, false if end of file was reached
+   */
+  virtual bool Read(SparsePage* page, dmlc::SeekStream* fi) = 0;
+  /*!
+   * \brief read only the segments we are interested in, advance fi to end of the block.
+   * \param page The page to load the data into.
+   * \param fi the input stream of the file
+   * \param sorted_index_set sorted index of segments we are interested in
+   * \return true of the loading as successful, false if end of file was reached
+   */
+  virtual bool Read(SparsePage* page,
+                    dmlc::SeekStream* fi,
+                    const std::vector<bst_uint>& sorted_index_set) = 0;
+  /*!
+   * \brief save the data to fo, when a page was written.
+   * \param fo output stream
+   */
+  virtual void Write(const SparsePage& page, dmlc::Stream* fo) const = 0;
+  /*!
+   * \brief Create sparse page of format.
+   * \return The created format functors.
+   */
+  static Format* Create(const std::string& name);
+  /*!
+   * \brief decide the format from cache prefix.
+   * \return format type of the cache prefix.
+   */
+  static std::string DecideFormat(const std::string& cache_prefix);
+};
+
+/*!
+ * \brief Registry entry for sparse page format.
+ */
+struct SparsePageFormatReg
+    : public dmlc::FunctionRegEntryBase<SparsePageFormatReg,
+                                        std::function<SparsePage::Format* ()> > {
+};
+
+/*!
+ * \brief Macro to register sparse page format.
+ *
+ * \code
+ * // example of registering a objective
+ * XGBOOST_REGISTER_SPARSE_PAGE_FORMAT(raw)
+ * .describe("Raw binary data format.")
+ * .set_body([]() {
+ *     return new RawFormat();
+ *   });
+ * \endcode
+ */
+#define XGBOOST_REGISTER_SPARSE_PAGE_FORMAT(Name)                       \
+  DMLC_REGISTRY_REGISTER(::xgboost::data::SparsePageFormatReg, SparsePageFormat, Name)
+
 }  // namespace data
 }  // namespace xgboost
 #endif  // XGBOOST_DATA_SPARSE_BATCH_PAGE_H_
diff --git a/src/data/sparse_page_dmatrix.cc b/src/data/sparse_page_dmatrix.cc
index ba4f566f5..e25ea6e25 100644
--- a/src/data/sparse_page_dmatrix.cc
+++ b/src/data/sparse_page_dmatrix.cc
@@ -17,20 +17,24 @@ namespace data {
 
 SparsePageDMatrix::ColPageIter::ColPageIter(std::unique_ptr<dmlc::SeekStream>&& fi)
     : fi_(std::move(fi)), page_(nullptr) {
-
-
   load_all_ = false;
+
+  std::string format;
+  CHECK(fi_->Read(&format)) << "Invalid page format";
+  format_.reset(SparsePage::Format::Create(format));
+  size_t fbegin = fi_->Tell();
+
   prefetcher_.Init([this](SparsePage** dptr) {
       if (*dptr == nullptr) {
         *dptr = new SparsePage();
       }
       if (load_all_) {
-        return (*dptr)->Load(fi_.get());
+        return format_->Read(*dptr, fi_.get());
       } else {
-        return (*dptr)->Load(fi_.get(), index_set_);
+        return format_->Read(*dptr, fi_.get(), index_set_);
       }
-    }, [this] () {
-      fi_->Seek(0);
+    }, [this, fbegin] () {
+      fi_->Seek(fbegin);
       index_set_ = set_index_set_;
       load_all_ = set_load_all_;
     });
@@ -222,6 +226,11 @@ void SparsePageDMatrix::InitColAccess(const std::vector<bool>& enabled,
 
   std::string col_data_name = cache_prefix_ + ".col.page";
   std::unique_ptr<dmlc::Stream> fo(dmlc::Stream::Create(col_data_name.c_str(), "w"));
+  // find format.
+  std::string name_format = SparsePage::Format::DecideFormat(cache_prefix_);
+  fo->Write(name_format);
+  std::unique_ptr<SparsePage::Format> format(SparsePage::Format::Create(name_format));
+
   double tstart = dmlc::GetTime();
   size_t bytes_write = 0;
   SparsePage* pcol = nullptr;
@@ -230,7 +239,7 @@ void SparsePageDMatrix::InitColAccess(const std::vector<bool>& enabled,
     for (size_t i = 0; i < pcol->Size(); ++i) {
       col_size_[i] += pcol->offset[i + 1] - pcol->offset[i];
     }
-    pcol->Save(fo.get());
+    format->Write(*pcol, fo.get());
     size_t spage = pcol->MemCostBytes();
     bytes_write += spage;
     double tdiff = dmlc::GetTime() - tstart;
diff --git a/src/data/sparse_page_dmatrix.h b/src/data/sparse_page_dmatrix.h
index 12e9ae165..9d0a2e344 100644
--- a/src/data/sparse_page_dmatrix.h
+++ b/src/data/sparse_page_dmatrix.h
@@ -92,6 +92,10 @@ class SparsePageDMatrix : public DMatrix {
    private:
     // data file pointer.
     std::unique_ptr<dmlc::SeekStream> fi_;
+    // the temp page.
+    SparsePage* page_;
+    // page format.
+    std::unique_ptr<SparsePage::Format> format_;
     // The index set to be loaded.
     std::vector<bst_uint> index_set_;
     // The index set by the outsiders
@@ -100,8 +104,6 @@ class SparsePageDMatrix : public DMatrix {
     bool set_load_all_, load_all_;
     // data prefetcher.
     dmlc::ThreadedIter<SparsePage> prefetcher_;
-    // the temp page.
-    SparsePage* page_;
     // temporal space for batch
     ColBatch out_;
     // the pointer data.
diff --git a/src/data/sparse_page_raw_format.cc b/src/data/sparse_page_raw_format.cc
new file mode 100644
index 000000000..867ffad1c
--- /dev/null
+++ b/src/data/sparse_page_raw_format.cc
@@ -0,0 +1,96 @@
+/*!
+ * Copyright (c) 2015 by Contributors
+ * \file sparse_page_raw_format.cc
+ *  Raw binary format of sparse page.
+ */
+#include <xgboost/data.h>
+#include "./sparse_batch_page.h"
+
+namespace xgboost {
+namespace data {
+
+class SparsePageRawFormat : public SparsePage::Format {
+ public:
+  bool Read(SparsePage* page, dmlc::SeekStream* fi) override {
+    if (!fi->Read(&(page->offset))) return false;
+    CHECK_NE(page->offset.size(), 0) << "Invalid SparsePage file";
+    page->data.resize(page->offset.back());
+    if (page->data.size() != 0) {
+      CHECK_EQ(fi->Read(dmlc::BeginPtr(page->data),
+                        (page->data).size() * sizeof(SparseBatch::Entry)),
+               (page->data).size() * sizeof(SparseBatch::Entry))
+          << "Invalid SparsePage file";
+    }
+    return true;
+  }
+
+  bool Read(SparsePage* page,
+            dmlc::SeekStream* fi,
+            const std::vector<bst_uint>& sorted_index_set) override {
+    if (!fi->Read(&disk_offset_)) return false;
+    // setup the offset
+    page->offset.clear();
+    page->offset.push_back(0);
+    for (size_t i = 0; i < sorted_index_set.size(); ++i) {
+      bst_uint fid = sorted_index_set[i];
+      CHECK_LT(fid + 1, disk_offset_.size());
+      size_t size = disk_offset_[fid + 1] - disk_offset_[fid];
+      page->offset.push_back(page->offset.back() + size);
+    }
+    page->data.resize(page->offset.back());
+    // read in the data
+    size_t begin = fi->Tell();
+    size_t curr_offset = 0;
+    for (size_t i = 0; i < sorted_index_set.size();) {
+      bst_uint fid = sorted_index_set[i];
+      if (disk_offset_[fid] != curr_offset) {
+        CHECK_GT(disk_offset_[fid], curr_offset);
+        fi->Seek(begin + disk_offset_[fid] * sizeof(SparseBatch::Entry));
+        curr_offset = disk_offset_[fid];
+      }
+      size_t j, size_to_read = 0;
+      for (j = i; j < sorted_index_set.size(); ++j) {
+        if (disk_offset_[sorted_index_set[j]] == disk_offset_[fid] + size_to_read) {
+          size_to_read += page->offset[j + 1] - page->offset[j];
+        } else {
+          break;
+        }
+      }
+
+      if (size_to_read != 0) {
+        CHECK_EQ(fi->Read(dmlc::BeginPtr(page->data) + page->offset[i],
+                          size_to_read * sizeof(SparseBatch::Entry)),
+                 size_to_read * sizeof(SparseBatch::Entry))
+            << "Invalid SparsePage file";
+        curr_offset += size_to_read;
+      }
+      i = j;
+    }
+    // seek to end of record
+    if (curr_offset != disk_offset_.back()) {
+      fi->Seek(begin + disk_offset_.back() * sizeof(SparseBatch::Entry));
+    }
+    return true;
+  }
+
+  void Write(const SparsePage& page, dmlc::Stream* fo) const override {
+    CHECK(page.offset.size() != 0 && page.offset[0] == 0);
+    CHECK_EQ(page.offset.back(), page.data.size());
+    fo->Write(page.offset);
+    if (page.data.size() != 0) {
+      fo->Write(dmlc::BeginPtr(page.data), page.data.size() * sizeof(SparseBatch::Entry));
+    }
+  }
+
+ private:
+  /*! \brief external memory column offset */
+  std::vector<size_t> disk_offset_;
+};
+
+XGBOOST_REGISTER_SPARSE_PAGE_FORMAT(raw)
+.describe("Raw binary data format.")
+.set_body([]() {
+    return new SparsePageRawFormat();
+  });
+}  // namespace data
+}  // namespace xgboost
diff --git a/src/data/sparse_page_source.cc b/src/data/sparse_page_source.cc
index 4ee6f17c4..8159d3807 100644
--- a/src/data/sparse_page_source.cc
+++ b/src/data/sparse_page_source.cc
@@ -24,12 +24,18 @@ SparsePageSource::SparsePageSource(const std::string& cache_prefix)
   // read in the cache files.
   std::string name_row = cache_prefix + ".row.page";
   fi_.reset(dmlc::SeekStream::CreateForRead(name_row.c_str()));
+
+  std::string format;
+  CHECK(fi_->Read(&format)) << "Invalid page format";
+  format_.reset(SparsePage::Format::Create(format));
+  size_t fbegin = fi_->Tell();
+
   prefetcher_.Init([this] (SparsePage** dptr) {
       if (*dptr == nullptr) {
         *dptr = new SparsePage();
       }
-      return (*dptr)->Load(fi_.get());
-    }, [this] () { fi_->Seek(0); });
+      return format_->Read(*dptr, fi_.get());
+    }, [this, fbegin] () { fi_->Seek(fbegin); });
 }
 
 SparsePageSource::~SparsePageSource() {
@@ -72,6 +78,10 @@ void SparsePageSource::Create(dmlc::Parser<uint32_t>* src,
   std::string name_info = cache_prefix;
   std::string name_row = cache_prefix + ".row.page";
   std::unique_ptr<dmlc::Stream> fo(dmlc::Stream::Create(name_row.c_str(), "w"));
+  std::string name_format = SparsePage::Format::DecideFormat(cache_prefix);
+  fo->Write(name_format);
+  std::unique_ptr<SparsePage::Format> format(SparsePage::Format::Create(name_format));
+
   MetaInfo info;
   SparsePage page;
   size_t bytes_write = 0;
@@ -95,7 +105,7 @@ void SparsePageSource::Create(dmlc::Parser<uint32_t>* src,
     page.Push(batch);
     if (page.MemCostBytes() >= kPageSize) {
       bytes_write += page.MemCostBytes();
-      page.Save(fo.get());
+      format->Write(page, fo.get());
       page.Clear();
       double tdiff = dmlc::GetTime() - tstart;
       LOG(CONSOLE) << "Writing to " << name_row << " in "
@@ -105,7 +115,7 @@ void SparsePageSource::Create(dmlc::Parser<uint32_t>* src,
   }
 
   if (page.data.size() != 0) {
-    page.Save(fo.get());
+    format->Write(page, fo.get());
   }
 
   fo.reset(dmlc::Stream::Create(name_info.c_str(), "w"));
@@ -122,6 +132,10 @@ void SparsePageSource::Create(DMatrix* src,
   std::string name_info = cache_prefix;
   std::string name_row = cache_prefix + ".row.page";
   std::unique_ptr<dmlc::Stream> fo(dmlc::Stream::Create(name_row.c_str(), "w"));
+  // find format.
+  std::string name_format = SparsePage::Format::DecideFormat(cache_prefix);
+  fo->Write(name_format);
+  std::unique_ptr<SparsePage::Format> format(SparsePage::Format::Create(name_format));
 
   SparsePage page;
   size_t bytes_write = 0;
@@ -132,7 +146,7 @@ void SparsePageSource::Create(DMatrix* src,
     page.Push(iter->Value());
     if (page.MemCostBytes() >= kPageSize) {
       bytes_write += page.MemCostBytes();
-      page.Save(fo.get());
+      format->Write(page, fo.get());
       page.Clear();
       double tdiff = dmlc::GetTime() - tstart;
       LOG(CONSOLE) << "Writing to " << name_row << " in "
@@ -142,7 +156,7 @@ void SparsePageSource::Create(DMatrix* src,
   }
 
   if (page.data.size() != 0) {
-    page.Save(fo.get());
+    format->Write(page, fo.get());
   }
 
   fo.reset(dmlc::Stream::Create(name_info.c_str(), "w"));
diff --git a/src/data/sparse_page_source.h b/src/data/sparse_page_source.h
index cdbfd9020..79c55b4ba 100644
--- a/src/data/sparse_page_source.h
+++ b/src/data/sparse_page_source.h
@@ -75,6 +75,8 @@ class SparsePageSource : public DataSource {
   std::string cache_prefix_;
   /*! \brief file pointer to the row blob file. */
   std::unique_ptr<dmlc::SeekStream> fi_;
+  /*! \brief Sparse page format file. */
+  std::unique_ptr<SparsePage::Format> format_;
   /*! \brief internal prefetcher. */
   dmlc::ThreadedIter<SparsePage> prefetcher_;
 };