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arangodb/arangod/VocBase/headers.cpp

632 lines
20 KiB
C++

////////////////////////////////////////////////////////////////////////////////
/// @brief datafiles
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2004-2013 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is triAGENS GmbH, Cologne, Germany
///
/// @author Dr. Frank Celler
/// @author Copyright 2011-2013, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "headers.h"
#include "BasicsC/logging.h"
#include "VocBase/primary-collection.h"
// -----------------------------------------------------------------------------
// --SECTION-- private defines
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup VocBase
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief minium number of headers per block
////////////////////////////////////////////////////////////////////////////////
#define BLOCK_SIZE_UNIT (128)
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- private types
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief headers
////////////////////////////////////////////////////////////////////////////////
typedef struct simple_headers_s {
TRI_headers_t base;
TRI_doc_mptr_t const* _freelist; // free headers
TRI_doc_mptr_t* _begin; // start pointer to list of allocated headers
TRI_doc_mptr_t* _end; // end pointer to list of allocated headers
size_t _nrAllocated; // number of allocated headers
size_t _nrLinked; // number of linked headers
int64_t _totalSize; // total size of markers for linked headers
TRI_vector_pointer_t _blocks;
}
simple_headers_t;
// -----------------------------------------------------------------------------
// --SECTION-- private functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief get the size (number of entries) for a block, based on a function
///
/// this adaptively increases the number of entries per block until a certain
/// threshold. the benefit of this is that small collections (with few
/// documents) only use little memory whereas bigger collections allocate new
/// blocks in bigger chunks.
/// the lowest value for the number of entries in a block is BLOCK_SIZE_UNIT,
/// the highest value is BLOCK_SIZE_UNIT << 8.
////////////////////////////////////////////////////////////////////////////////
static size_t GetBlockSize (const size_t blockNumber) {
if (blockNumber < 8) {
return (size_t) (BLOCK_SIZE_UNIT << blockNumber);
}
return (size_t) (BLOCK_SIZE_UNIT << 8);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief clears a header
////////////////////////////////////////////////////////////////////////////////
static void ClearHeader (TRI_headers_t* h,
TRI_doc_mptr_t* header) {
simple_headers_t* headers = (simple_headers_t*) h;
TRI_ASSERT_MAINTAINER(header != NULL);
memset(header, 0, sizeof(TRI_doc_mptr_t));
TRI_ASSERT_MAINTAINER(headers->_nrAllocated > 0);
headers->_nrAllocated--;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief moves an existing header to the end of the list
/// this is called when there is an update operation on a document
////////////////////////////////////////////////////////////////////////////////
static void MoveBackHeader (TRI_headers_t* h,
TRI_doc_mptr_t* header,
TRI_doc_mptr_t* old) {
simple_headers_t* headers = (simple_headers_t*) h;
int64_t oldSize;
int64_t newSize;
if (header == NULL) {
return;
}
TRI_ASSERT_MAINTAINER(headers->_nrAllocated > 0);
TRI_ASSERT_MAINTAINER(headers->_nrLinked > 0);
TRI_ASSERT_MAINTAINER(headers->_totalSize > 0);
// we have at least one element in the list
TRI_ASSERT_MAINTAINER(headers->_begin != NULL);
TRI_ASSERT_MAINTAINER(headers->_end != NULL);
TRI_ASSERT_MAINTAINER(header->_prev != header);
TRI_ASSERT_MAINTAINER(header->_next != header);
TRI_ASSERT_MAINTAINER(old != NULL);
TRI_ASSERT_MAINTAINER(old->_data != NULL);
newSize = (int64_t) (((TRI_df_marker_t*) header->_data)->_size);
oldSize = (int64_t) (((TRI_df_marker_t*) old->_data)->_size);
// we must adjust the size of the collection
headers->_totalSize += TRI_DF_ALIGN_BLOCK(newSize);
headers->_totalSize -= TRI_DF_ALIGN_BLOCK(oldSize);
if (headers->_end == header) {
// header is already at the end
TRI_ASSERT_MAINTAINER(header->_next == NULL);
return;
}
TRI_ASSERT_MAINTAINER(headers->_begin != headers->_end);
// unlink the element
if (header->_prev != NULL) {
header->_prev->_next = header->_next;
}
if (header->_next != NULL) {
header->_next->_prev = header->_prev;
}
if (headers->_begin == header) {
TRI_ASSERT_MAINTAINER(header->_next != NULL);
headers->_begin = header->_next;
}
header->_prev = headers->_end;
header->_next = NULL;
headers->_end = header;
header->_prev->_next = header;
TRI_ASSERT_MAINTAINER(headers->_begin != NULL);
TRI_ASSERT_MAINTAINER(headers->_end != NULL);
TRI_ASSERT_MAINTAINER(header->_prev != header);
TRI_ASSERT_MAINTAINER(header->_next != header);
TRI_ASSERT_MAINTAINER(headers->_totalSize > 0);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief unlinks a header from the list, without freeing it
////////////////////////////////////////////////////////////////////////////////
static void UnlinkHeader (TRI_headers_t* h,
TRI_doc_mptr_t* header) {
simple_headers_t* headers = (simple_headers_t*) h;
int64_t size;
TRI_ASSERT_MAINTAINER(header != NULL);
TRI_ASSERT_MAINTAINER(header->_data != NULL);
TRI_ASSERT_MAINTAINER(header->_prev != header);
TRI_ASSERT_MAINTAINER(header->_next != header);
size = (int64_t) ((TRI_df_marker_t*) header->_data)->_size;
TRI_ASSERT_MAINTAINER(size > 0);
// unlink the header
if (header->_prev != NULL) {
header->_prev->_next = header->_next;
}
if (header->_next != NULL) {
header->_next->_prev = header->_prev;
}
// adjust begin & end pointers
if (headers->_begin == header) {
headers->_begin = header->_next;
}
if (headers->_end == header) {
headers->_end = header->_prev;
}
TRI_ASSERT_MAINTAINER(headers->_begin != header);
TRI_ASSERT_MAINTAINER(headers->_end != header);
TRI_ASSERT_MAINTAINER(headers->_nrLinked > 0);
headers->_nrLinked--;
headers->_totalSize -= TRI_DF_ALIGN_BLOCK(size);
if (headers->_nrLinked == 0) {
TRI_ASSERT_MAINTAINER(headers->_begin == NULL);
TRI_ASSERT_MAINTAINER(headers->_end == NULL);
TRI_ASSERT_MAINTAINER(headers->_totalSize == 0);
}
else {
TRI_ASSERT_MAINTAINER(headers->_begin != NULL);
TRI_ASSERT_MAINTAINER(headers->_end != NULL);
TRI_ASSERT_MAINTAINER(headers->_totalSize > 0);
}
TRI_ASSERT_MAINTAINER(header->_prev != header);
TRI_ASSERT_MAINTAINER(header->_next != header);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief moves a header around in the list, using its previous position
/// (specified in "old")
////////////////////////////////////////////////////////////////////////////////
static void MoveHeader (TRI_headers_t* h,
TRI_doc_mptr_t* header,
TRI_doc_mptr_t* old) {
simple_headers_t* headers = (simple_headers_t*) h;
int64_t newSize;
int64_t oldSize;
if (header == NULL) {
return;
}
TRI_ASSERT_MAINTAINER(headers->_nrAllocated > 0);
TRI_ASSERT_MAINTAINER(header->_prev != header);
TRI_ASSERT_MAINTAINER(header->_next != header);
TRI_ASSERT_MAINTAINER(header->_data != NULL);
TRI_ASSERT_MAINTAINER(((TRI_df_marker_t*) header->_data)->_size > 0);
TRI_ASSERT_MAINTAINER(old != NULL);
TRI_ASSERT_MAINTAINER(old->_data != NULL);
newSize = (int64_t) (((TRI_df_marker_t*) header->_data)->_size);
oldSize = (int64_t) (((TRI_df_marker_t*) old->_data)->_size);
headers->_totalSize -= TRI_DF_ALIGN_BLOCK(newSize);
headers->_totalSize += TRI_DF_ALIGN_BLOCK(oldSize);
// adjust list start and end pointers
if (old->_prev == NULL) {
headers->_begin = header;
}
else if (headers->_begin == header) {
headers->_begin = header->_next;
}
if (old->_next == NULL) {
headers->_end = header;
}
else if (headers->_end == header) {
headers->_end = header->_prev;
}
if (header->_prev != NULL) {
if (header->_prev == old->_next) {
header->_prev->_next = NULL;
}
else {
header->_prev->_next = header->_next;
}
}
if (header->_next != NULL) {
if (header->_next == old->_prev) {
header->_next->_prev = NULL;
}
else {
header->_next->_prev = header->_prev;
}
}
if (old->_prev != NULL) {
old->_prev->_next = header;
header->_prev = old->_prev;
}
else {
header->_prev = NULL;
}
if (old->_next != NULL) {
old->_next->_prev = header;
header->_next = old->_next;
}
else {
header->_next = NULL;
}
TRI_ASSERT_MAINTAINER(headers->_begin != NULL);
TRI_ASSERT_MAINTAINER(headers->_end != NULL);
TRI_ASSERT_MAINTAINER(header->_prev != header);
TRI_ASSERT_MAINTAINER(header->_next != header);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief moves a header back into the list, using its previous position
/// (specified in "old")
////////////////////////////////////////////////////////////////////////////////
static void RelinkHeader (TRI_headers_t* h,
TRI_doc_mptr_t* header,
TRI_doc_mptr_t* old) {
simple_headers_t* headers = (simple_headers_t*) h;
int64_t size;
if (header == NULL) {
return;
}
TRI_ASSERT_MAINTAINER(header->_data != NULL);
size = (int64_t) ((TRI_df_marker_t*) header->_data)->_size;
TRI_ASSERT_MAINTAINER(size > 0);
TRI_ASSERT_MAINTAINER(headers->_begin != header);
TRI_ASSERT_MAINTAINER(headers->_end != header);
MoveHeader(h, header, old);
headers->_nrLinked++;
headers->_totalSize += TRI_DF_ALIGN_BLOCK(size);
TRI_ASSERT_MAINTAINER(headers->_totalSize > 0);
TRI_ASSERT_MAINTAINER(header->_prev != header);
TRI_ASSERT_MAINTAINER(header->_next != header);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief requests a new header
////////////////////////////////////////////////////////////////////////////////
static TRI_doc_mptr_t* RequestHeader (TRI_headers_t* h,
size_t size) {
simple_headers_t* headers = (simple_headers_t*) h;
char const* header;
assert(size > 0);
if (headers->_freelist == NULL) {
size_t blockSize = GetBlockSize(headers->_blocks._length);
TRI_ASSERT_MAINTAINER(blockSize > 0);
// initialise the memory with 0's
char* begin = static_cast<char*>(TRI_Allocate(TRI_UNKNOWN_MEM_ZONE, blockSize * sizeof(TRI_doc_mptr_t), true));
// out of memory
if (begin == NULL) {
TRI_set_errno(TRI_ERROR_OUT_OF_MEMORY);
return NULL;
}
char* ptr = begin + sizeof(TRI_doc_mptr_t) * (blockSize - 1);
header = NULL;
for (; begin <= ptr; ptr -= sizeof(TRI_doc_mptr_t)) {
((TRI_doc_mptr_t*) ptr)->_data = header;
header = ptr;
}
TRI_ASSERT_MAINTAINER(headers != NULL);
headers->_freelist = (TRI_doc_mptr_t*) header;
TRI_PushBackVectorPointer(&headers->_blocks, begin);
}
TRI_ASSERT_MAINTAINER(headers->_freelist != NULL);
TRI_doc_mptr_t* result = const_cast<TRI_doc_mptr_t*>(headers->_freelist);
TRI_ASSERT_MAINTAINER(result != NULL);
headers->_freelist = static_cast<TRI_doc_mptr_t const*>(result->_data);
result->_data = NULL;
// put new header at the end of the list
if (headers->_begin == NULL) {
// list of headers is empty
TRI_ASSERT_MAINTAINER(headers->_nrLinked == 0);
TRI_ASSERT_MAINTAINER(headers->_totalSize == 0);
headers->_begin = result;
headers->_end = result;
result->_prev = NULL;
result->_next = NULL;
}
else {
// list is not empty
TRI_ASSERT_MAINTAINER(headers->_nrLinked > 0);
TRI_ASSERT_MAINTAINER(headers->_totalSize > 0);
TRI_ASSERT_MAINTAINER(headers->_nrAllocated > 0);
TRI_ASSERT_MAINTAINER(headers->_begin != NULL);
TRI_ASSERT_MAINTAINER(headers->_end != NULL);
headers->_end->_next = result;
result->_prev = headers->_end;
result->_next = NULL;
headers->_end = result;
}
headers->_nrAllocated++;
headers->_nrLinked++;
headers->_totalSize += (int64_t) TRI_DF_ALIGN_BLOCK(size);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief releases a header, putting it back onto the freelist
////////////////////////////////////////////////////////////////////////////////
static void ReleaseHeader (TRI_headers_t* h,
TRI_doc_mptr_t* header,
bool unlinkHeader) {
simple_headers_t* headers = (simple_headers_t*) h;
if (header == NULL) {
return;
}
if (unlinkHeader) {
UnlinkHeader(h, header);
}
ClearHeader(h, header);
header->_data = headers->_freelist;
headers->_freelist = header;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief return the element at the head of the list
///
/// note: the element returned might be NULL
////////////////////////////////////////////////////////////////////////////////
static TRI_doc_mptr_t* FrontHeaders (TRI_headers_t const* h) {
simple_headers_t* headers = (simple_headers_t*) h;
return headers->_begin;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief return the element at the tail of the list
///
/// note: the element returned might be NULL
////////////////////////////////////////////////////////////////////////////////
static TRI_doc_mptr_t* BackHeaders (TRI_headers_t const* h) {
simple_headers_t* headers = (simple_headers_t*) h;
return headers->_end;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief return the number of linked headers
////////////////////////////////////////////////////////////////////////////////
static size_t CountHeaders (TRI_headers_t const* h) {
simple_headers_t* headers = (simple_headers_t*) h;
return headers->_nrLinked;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief return the total size of linked headers
////////////////////////////////////////////////////////////////////////////////
static int64_t TotalSizeHeaders (TRI_headers_t const* h) {
simple_headers_t* headers = (simple_headers_t*) h;
return (int64_t) headers->_totalSize;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief dump all headers
////////////////////////////////////////////////////////////////////////////////
#ifdef TRI_ENABLE_MAINTAINER_MODE
static void DumpHeaders (TRI_headers_t const* h) {
simple_headers_t* headers = (simple_headers_t*) h;
TRI_doc_mptr_t* next = headers->_begin;
size_t i = 0;
printf("number of allocated headers: %lu\n", (unsigned long) headers->_nrAllocated);
printf("number of linked headers: %lu\n", (unsigned long) headers->_nrLinked);
printf("total size: %lld\n", (long long) headers->_totalSize);
printf("begin ptr: %p\n", headers->_begin);
printf("end ptr: %p\n", headers->_end);
while (next != NULL) {
printf("- header #%lu: ptr: %p, prev: %p, next: %p, key: %s\n",
(unsigned long) i,
next,
next->_prev,
next->_next,
next->_key);
i++;
if (next->_next == NULL) {
TRI_ASSERT_MAINTAINER(next == headers->_end);
}
next = next->_next;
}
TRI_ASSERT_MAINTAINER(i == headers->_nrLinked);
}
#endif
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// -----------------------------------------------------------------------------
// --SECTION-- public functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @addtogroup VocBase
/// @{
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
/// @brief creates a new simple headers structures
////////////////////////////////////////////////////////////////////////////////
TRI_headers_t* TRI_CreateSimpleHeaders () {
simple_headers_t* headers = static_cast<simple_headers_t*>(TRI_Allocate(TRI_UNKNOWN_MEM_ZONE, sizeof(simple_headers_t), false));
if (headers == NULL) {
TRI_set_errno(TRI_ERROR_OUT_OF_MEMORY);
return NULL;
}
headers->_freelist = NULL;
headers->_begin = NULL;
headers->_end = NULL;
headers->_nrAllocated = 0;
headers->_nrLinked = 0;
headers->_totalSize = 0;
headers->base.request = RequestHeader;
headers->base.release = ReleaseHeader;
headers->base.moveBack = MoveBackHeader;
headers->base.move = MoveHeader;
headers->base.relink = RelinkHeader;
headers->base.unlink = UnlinkHeader;
headers->base.front = FrontHeaders;
headers->base.back = BackHeaders;
headers->base.count = CountHeaders;
headers->base.size = TotalSizeHeaders;
#ifdef TRI_ENABLE_MAINTAINER_MODE
headers->base.dump = DumpHeaders;
#endif
TRI_InitVectorPointer2(&headers->_blocks, TRI_UNKNOWN_MEM_ZONE, 8);
return &headers->base;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys a simple headers structures, but does not free the pointer
////////////////////////////////////////////////////////////////////////////////
void TRI_DestroySimpleHeaders (TRI_headers_t* h) {
simple_headers_t* headers = (simple_headers_t*) h;
size_t i;
for (i = 0; i < headers->_blocks._length; ++i) {
TRI_Free(TRI_UNKNOWN_MEM_ZONE, headers->_blocks._buffer[i]);
}
headers->_nrAllocated = 0;
headers->_nrLinked = 0;
headers->_totalSize = 0;
TRI_DestroyVectorPointer(&headers->_blocks);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroys a simple headers structures, but does not free the pointer
////////////////////////////////////////////////////////////////////////////////
void TRI_FreeSimpleHeaders (TRI_headers_t* headers) {
TRI_DestroySimpleHeaders(headers);
TRI_Free(TRI_UNKNOWN_MEM_ZONE, headers);
}
////////////////////////////////////////////////////////////////////////////////
/// @}
////////////////////////////////////////////////////////////////////////////////
// Local Variables:
// mode: outline-minor
// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @addtogroup\\|/// @page\\|// --SECTION--\\|/// @\\}"
// End: