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Overview
Comment:When using a temporary file for a statement journal, store the first 64KiB in memory. If the file grows larger than that, flush it to disk and free the memory. Hardcoding to 64KiB is just an experiment to check that the memjournal.c code works.
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SHA1: 44b2dc18e200e87cf062cb8f1659727c53fa36e9
User & Date: dan 2016-02-29 20:18:21.986
Context
2016-03-03
21:29
Merge the latest updates from trunk. (check-in: 55c00f716d user: drh tags: memjournal-exp)
2016-02-29
20:18
When using a temporary file for a statement journal, store the first 64KiB in memory. If the file grows larger than that, flush it to disk and free the memory. Hardcoding to 64KiB is just an experiment to check that the memjournal.c code works. (check-in: 44b2dc18e2 user: dan tags: memjournal-exp)
20:00
Fix minor problems with new code in memjournal.c. (check-in: 9fd3f7b9c9 user: dan tags: memjournal-exp)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/memjournal.c.
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){
  MemJournal *p = (MemJournal*)pJfd;

  /* Zero the file-handle object. If nBuf was passed zero, initialize
  ** it using the sqlite3OsOpen() function of the underlying VFS. In this
  ** case none of the code in this module is executed as a result of calls
  ** made on the journal file-handle.  */
  memset(p, 0, sizeof(MemJournal) + pVfs ? pVfs->szOsFile : 0);
  if( nBuf==0 ){
    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
  }

  if( nBuf>0 ){
    p->nChunkSize = nBuf;
  }else{








|








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){
  MemJournal *p = (MemJournal*)pJfd;

  /* Zero the file-handle object. If nBuf was passed zero, initialize
  ** it using the sqlite3OsOpen() function of the underlying VFS. In this
  ** case none of the code in this module is executed as a result of calls
  ** made on the journal file-handle.  */
  memset(p, 0, sizeof(MemJournal) + (pVfs ? pVfs->szOsFile : 0));
  if( nBuf==0 ){
    return sqlite3OsOpen(pVfs, zName, pJfd, flags, 0);
  }

  if( nBuf>0 ){
    p->nChunkSize = nBuf;
  }else{
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Changes to src/pager.c.
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** SQLITE_OK is returned if everything goes according to plan. An 
** SQLITE_IOERR_XXX error code is returned if a call to sqlite3OsOpen() 
** fails.
*/
static int openSubJournal(Pager *pPager){
  int rc = SQLITE_OK;
  if( !isOpen(pPager->sjfd) ){




    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY || pPager->subjInMemory ){
      sqlite3MemJournalOpen(pPager->sjfd);
    }else{
      rc = pagerOpentemp(pPager, pPager->sjfd, SQLITE_OPEN_SUBJOURNAL);

    }

  }
  return rc;
}

/*
** Append a record of the current state of page pPg to the sub-journal. 
**








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** SQLITE_OK is returned if everything goes according to plan. An 
** SQLITE_IOERR_XXX error code is returned if a call to sqlite3OsOpen() 
** fails.
*/
static int openSubJournal(Pager *pPager){
  int rc = SQLITE_OK;
  if( !isOpen(pPager->sjfd) ){
    const int flags =  SQLITE_OPEN_SUBJOURNAL | SQLITE_OPEN_READWRITE 
      | SQLITE_OPEN_CREATE | SQLITE_OPEN_EXCLUSIVE 
      | SQLITE_OPEN_DELETEONCLOSE;
    int nBuf = 64*1024;
    if( pPager->journalMode==PAGER_JOURNALMODE_MEMORY || pPager->subjInMemory ){



      nBuf = -1;
    }
    rc = sqlite3JournalOpen(pPager->pVfs, 0, pPager->sjfd, flags, nBuf);
  }
  return rc;
}

/*
** Append a record of the current state of page pPg to the sub-journal. 
**
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