Пример #1
0
        /// <summary>
        /// Save all dirty pages to disk
        /// </summary>
        public void Commit()
        {
            // get header page
            var header = _pager.GetPage <HeaderPage>(0);

            // set final datafile length (optimize page writes)
            _disk.SetLength(BasePage.GetSizeOfPages(header.LastPageID + 1));

            // write all dirty pages in data file
            foreach (var page in _pager.GetDirtyPages())
            {
                // first write in journal file original data
                _disk.WriteJournal(page.PageID, page.DiskData);

                // then writes no datafile new changed pages
                // page.WritePage() updated DiskData with new rendered buffer
                _disk.WritePage(page.PageID, _crypto == null || page.PageID == 0 ? page.WritePage() : _crypto.Encrypt(page.WritePage()));

                // mark page as clean (is now saved in disk)
                page.IsDirty = false;
            }

            // discard journal file
            _disk.ClearJournal();
        }
Пример #2
0
        /// <summary>
        /// Save all dirty pages to disk
        /// </summary>
        public void Commit()
        {
            // get header page
            var header = _pager.GetPage <HeaderPage>(0);

            // increase file changeID (back to 0 when overflow)
            header.ChangeID = header.ChangeID == ushort.MaxValue ? (ushort)0 : (ushort)(header.ChangeID + (ushort)1);

            // mark header as dirty
            _pager.SetDirty(header);

            // write journal file
            _disk.WriteJournal(_cache.GetDirtyPages()
                               .Select(x => x.DiskData)
                               .Where(x => x.Length > 0)
                               .ToList());

            // enter in exclusive lock mode to write on disk
            using (_locker.Exclusive())
            {
                // set final datafile length (optimize page writes)
                _disk.SetLength(BasePage.GetSizeOfPages(header.LastPageID + 1));

                foreach (var page in _cache.GetDirtyPages())
                {
                    // page.WritePage() updated DiskData with new rendered buffer
                    var buffer = _crypto == null || page.PageID == 0 ?
                                 page.WritePage() :
                                 _crypto.Encrypt(page.WritePage());

                    _disk.WritePage(page.PageID, buffer);
                }

                // mark all dirty pages in clean pages (all are persisted in disk and are valid pages)
                _cache.MarkDirtyAsClean();

                // ensure all pages from OS cache has been persisted on medium
                _disk.Flush();

                // discard journal file
                _disk.ClearJournal();
            }
        }
        /// <summary>
        ///     Save all dirty pages to disk - do not touch on lock disk
        /// </summary>
        private void Save()
        {
            // get header and mark as dirty
            var header = _pager.GetPage <HeaderPage>(0, true);

            // increase file changeID (back to 0 when overflow)
            header.ChangeID = header.ChangeID == ushort.MaxValue ? (ushort)0 : (ushort)(header.ChangeID + 1);

            // set final datafile length (optimize page writes)
            _disk.SetLength(BasePage.GetSizeOfPages(header.LastPageID + 1));

            // write all dirty pages in data file
            foreach (var page in _cache.GetDirtyPages())
            {
                _disk.WritePage(page.PageID, page.WritePage());
            }
        }
Пример #4
0
        /// <summary>
        /// Save all dirty pages to disk
        /// </summary>
        public void PersistDirtyPages()
        {
            // get header page
            var header = _pager.GetPage <HeaderPage>(0);

            // increase file changeID (back to 0 when overflow)
            header.ChangeID = header.ChangeID == ushort.MaxValue ? (ushort)0 : (ushort)(header.ChangeID + (ushort)1);

            // mark header as dirty
            _pager.SetDirty(header);

            _log.Write(Logger.Disk, "begin disk operations - changeID: {0}", header.ChangeID);

            // write journal file in desc order to header be last page in disk
            if (_disk.IsJournalEnabled)
            {
                _disk.WriteJournal(_cache.GetDirtyPages()
                                   .OrderByDescending(x => x.PageID)
                                   .Select(x => x.DiskData)
                                   .Where(x => x.Length > 0)
                                   .ToList(), header.LastPageID);

                // mark header as recovery before start writing (in journal, must keep recovery = false)
                header.Recovery = true;
            }
            else
            {
                // if no journal extend, resize file here to fast writes
                _disk.SetLength(BasePage.GetSizeOfPages(header.LastPageID + 1));
            }

            // get all dirty page stating from Header page (SortedList)
            // header page (id=0) always must be first page to write on disk because it's will mark disk as "in recovery"
            foreach (var page in _cache.GetDirtyPages())
            {
                // page.WritePage() updated DiskData with new rendered buffer
                var buffer = _crypto == null || page.PageID == 0 ?
                             page.WritePage() :
                             _crypto.Encrypt(page.WritePage());

                _disk.WritePage(page.PageID, buffer);
            }

            if (_disk.IsJournalEnabled)
            {
                // re-write header page but now with recovery=false
                header.Recovery = false;

                _log.Write(Logger.Disk, "re-write header page now with recovery = false");

                _disk.WritePage(0, header.WritePage());
            }

            // mark all dirty pages as clean pages (all are persisted in disk and are valid pages)
            _cache.MarkDirtyAsClean();

            // flush all data direct to disk
            _disk.Flush();

            // discard journal file
            _disk.ClearJournal(header.LastPageID);
        }