SQLite4  Check-in [340c9dcd22]

  } aParam[] = {
    { "autoflush",        0, LSM_CONFIG_AUTOFLUSH },
    { "page_size",        0, LSM_CONFIG_PAGE_SIZE },
    { "block_size",       0, LSM_CONFIG_BLOCK_SIZE },
    { "safety",           0, LSM_CONFIG_SAFETY },
    { "autowork",         0, LSM_CONFIG_AUTOWORK },
    { "autocheckpoint",   0, LSM_CONFIG_AUTOCHECKPOINT },

    { "mmap",             0, LSM_CONFIG_MMAP },
    { "use_log",          0, LSM_CONFIG_USE_LOG },
    { "automerge",        0, LSM_CONFIG_AUTOMERGE },
    { "max_freelist",     0, LSM_CONFIG_MAX_FREELIST },
    { "multi_proc",       0, LSM_CONFIG_MULTIPLE_PROCESSES },
    { "worker_automerge", 1, LSM_CONFIG_AUTOMERGE },
    { "test_no_recovery", 0, TEST_NO_RECOVERY },

}

int test_lsm_small_open(
  const char *zFile, 
  int bClear, 
  TestDb **ppDb
){
  const char *zCfg = "page_size=256 block_size=64";
  return testLsmOpen(zCfg, zFile, bClear, ppDb);
}

int test_lsm_lomem_open(
  const char *zFilename, 
  int bClear, 
  TestDb **ppDb
){
    /* "max_freelist=4 autocheckpoint=32" */
  const char *zCfg = 
    "page_size=256 block_size=64 autoflush=16 "
    "autocheckpoint=32"
    "mmap=0 "
  ;
  return testLsmOpen(zCfg, zFilename, bClear, ppDb);
}

int test_lsm_zip_open(
  const char *zFilename, 
  int bClear, 
  TestDb **ppDb
){
  const char *zCfg = 
    "page_size=256 block_size=64 autoflush=16 "
    "autocheckpoint=32 compression=1 mmap=0 "
  ;
  return testLsmOpen(zCfg, zFilename, bClear, ppDb);
}

lsm_db *tdb_lsm(TestDb *pDb){
  if( pDb->pMethods->xClose==test_lsm_close ){
    return ((LsmDb *)pDb)->db;

*/
int lsm_config(lsm_db *, int, ...);

/*
** The following values may be passed as the second argument to lsm_config().
**
** LSM_CONFIG_AUTOFLUSH:
**   A read/write integer parameter. 
**
**   This value determines the amount of data allowed to accumulate in a
**   live in-memory tree before it is marked as old. After committing a
**   transaction, a connection checks if the size of the live in-memory tree,
**   including data structure overhead, is greater than the value of this
**   option in KB. If it is, and there is not already an old in-memory tree,
**   the live in-memory tree is marked as old.
**
**   The maximum allowable value is 1048576 (1GB). There is no minimum 
**   value. If this parameter is set to zero, then an attempt is made to
**   mark the live in-memory tree as old after each transaction is committed.
**
**   The default value is 1024 (1MB).
**
** LSM_CONFIG_PAGE_SIZE:
**   A read/write integer parameter. This parameter may only be set before
**   lsm_open() has been called.
**
** LSM_CONFIG_BLOCK_SIZE:
**   A read/write integer parameter. 
**
**   This parameter may only be set before lsm_open() has been called. It
**   must be set to a power of two between 64 and 65536, inclusive (block 
**   sizes between 64KB and 64MB).
**
**   If the connection creates a new database, the block size of the new
**   database is set to the value of this option in KB. After lsm_open()
**   has been called, querying this parameter returns the actual block
**   size of the opened database.
**
**   The default value is 1024 (1MB blocks).
**
** LSM_CONFIG_SAFETY:
**   A read/write integer parameter. Valid values are 0, 1 (the default) 
**   and 2. This parameter determines how robust the database is in the
**   face of a system crash (e.g. a power failure or operating system 
**   crash). As follows:
**

**                 contains all successfully committed transactions.
**
** LSM_CONFIG_AUTOWORK:
**   A read/write integer parameter.
**
** LSM_CONFIG_AUTOCHECKPOINT:
**   A read/write integer parameter.
**
**   If this option is set to non-zero value N, then a checkpoint is
**   automatically attempted after each N KB of data have been written to 
**   the database file.
**
**   The amount of uncheckpointed data already written to the database file
**   is a global parameter. After performing database work (writing to the
**   database file), the process checks if the total amount of uncheckpointed 
**   data exceeds the value of this paramter. If so, a checkpoint is performed.
**   This means that this option may cause the connection to perform a 
**   checkpoint even if the current connection has itself written very little
**   data into the database file.
**
**   The default value is 2048 (checkpoint every 2MB).
**
** LSM_CONFIG_MMAP:
**   A read/write integer parameter. True to use mmap() to access the 
**   database file. False otherwise.
**
** LSM_CONFIG_USE_LOG:
**   A read/write boolean parameter. True (the default) to use the log

**   content.
*/
#define LSM_CONFIG_AUTOFLUSH           1
#define LSM_CONFIG_PAGE_SIZE           2
#define LSM_CONFIG_SAFETY              3
#define LSM_CONFIG_BLOCK_SIZE          4
#define LSM_CONFIG_AUTOWORK            5

#define LSM_CONFIG_MMAP                7
#define LSM_CONFIG_USE_LOG             8
#define LSM_CONFIG_AUTOMERGE           9
#define LSM_CONFIG_MAX_FREELIST       10
#define LSM_CONFIG_MULTIPLE_PROCESSES 11
#define LSM_CONFIG_AUTOCHECKPOINT     12
#define LSM_CONFIG_SET_COMPRESSION    13

/*
** Default values for various data structure parameters. These may be
** overridden by calls to lsm_config().
*/
#define LSM_DFLT_PAGE_SIZE          (4 * 1024)
#define LSM_DFLT_BLOCK_SIZE         (1 * 1024 * 1024)
#define LSM_DFLT_AUTOFLUSH          (1 * 1024 * 1024)
#define LSM_DFLT_AUTOCHECKPOINT     (i64)(2 * 1024 * 1024)
#define LSM_DFLT_AUTOWORK           1
#define LSM_DFLT_LOG_SIZE           (128*1024)
#define LSM_DFLT_AUTOMERGE          4
#define LSM_DFLT_SAFETY             LSM_SAFETY_NORMAL
#define LSM_DFLT_MMAP               LSM_IS_64_BIT
#define LSM_DFLT_MULTIPLE_PROCESSES 1
#define LSM_DFLT_USE_LOG            1

  int (*xCmp)(void *, int, void *, int);    /* Compare function */

  /* Values configured by calls to lsm_config */
  int eSafety;                    /* LSM_SAFETY_OFF, NORMAL or FULL */
  int bAutowork;                  /* Configured by LSM_CONFIG_AUTOWORK */
  int nTreeLimit;                 /* Configured by LSM_CONFIG_AUTOFLUSH */
  int nMerge;                     /* Configured by LSM_CONFIG_AUTOMERGE */

  int bUseLog;                    /* Configured by LSM_CONFIG_USE_LOG */
  int nDfltPgsz;                  /* Configured by LSM_CONFIG_PAGE_SIZE */
  int nDfltBlksz;                 /* Configured by LSM_CONFIG_BLOCK_SIZE */
  int nMaxFreelist;               /* Configured by LSM_CONFIG_MAX_FREELIST */
  int bMmap;                      /* Configured by LSM_CONFIG_MMAP */
  i64 nAutockpt;                  /* Configured by LSM_CONFIG_AUTOCHECKPOINT */
  int bMultiProc;                 /* Configured by L_C_MULTIPLE_PROCESSES */
  lsm_compress compress;          /* Compression callbacks */

  /* Sub-system handles */
  FileSystem *pFS;                /* On-disk portion of database */
  Database *pDatabase;            /* Database shared data */

#define LSM_LOG_WRITE_CKSUM  0x07
#define LSM_LOG_DELETE       0x08
#define LSM_LOG_DELETE_CKSUM 0x09

/* Require a checksum every 32KB. */
#define LSM_CKSUM_MAXDATA (32*1024)

/* Do not wrap a log file smaller than this in bytes. */
#define LSM_MIN_LOGWRAP      (128*1024)

/*
** szSector:
**   Commit records must be aligned to end on szSector boundaries. If
**   the safety-mode is set to NORMAL or OFF, this value is 1. Otherwise,
**   if the safety-mode is set to FULL, it is the size of the file-system
**   sectors as reported by lsmFsSectorSize().
*/

  }else{
    pNew->szSector = 1;
  }

  /* There are now three scenarios:
  **
  **   1) Regions 0 and 1 are both zero bytes in size and region 2 begins
  **      at a file offset greater than LSM_MIN_LOGWRAP. In this case, wrap

  **      around to the start and write data into the start of the log file. 
  **
  **   2) Region 1 is zero bytes in size and region 2 occurs earlier in the 
  **      file than region 0. In this case, append data to region 2, but
  **      remember to jump over region 1 if required.
  **
  **   3) Region 2 is the last in the file. Append to it.
  */
  aReg = &pDb->treehdr.log.aRegion[0];

  assert( aReg[0].iEnd==0 || aReg[0].iEnd>aReg[0].iStart );
  assert( aReg[1].iEnd==0 || aReg[1].iEnd>aReg[1].iStart );

  pNew->cksum0 = pDb->treehdr.log.cksum0;
  pNew->cksum1 = pDb->treehdr.log.cksum1;

  if( aReg[0].iEnd==0 && aReg[1].iEnd==0 && aReg[2].iStart>=LSM_MIN_LOGWRAP ){
    /* Case 1. Wrap around to the start of the file. Write an LSM_LOG_JUMP 
    ** into the log file in this case. Pad it out to 8 bytes using a PAD2
    ** record so that the checksums can be updated immediately.  */
    u8 aJump[] = { 
      LSM_LOG_PAD2, 0x04, 0x00, 0x00, 0x00, 0x00, LSM_LOG_JUMP, 0x00 
    };

  /* Initialize the new object */
  pDb->pEnv = pEnv;
  pDb->nTreeLimit = LSM_DFLT_AUTOFLUSH;
  pDb->nAutockpt = LSM_DFLT_AUTOCHECKPOINT;
  pDb->bAutowork = LSM_DFLT_AUTOWORK;
  pDb->eSafety = LSM_DFLT_SAFETY;
  pDb->xCmp = xCmp;

  pDb->nDfltPgsz = LSM_DFLT_PAGE_SIZE;
  pDb->nDfltBlksz = LSM_DFLT_BLOCK_SIZE;
  pDb->nMerge = LSM_DFLT_AUTOMERGE;
  pDb->nMaxFreelist = LSM_MAX_FREELIST_ENTRIES;
  pDb->bUseLog = LSM_DFLT_USE_LOG;
  pDb->iReader = -1;
  pDb->bMultiProc = LSM_DFLT_MULTIPLE_PROCESSES;

int lsm_config(lsm_db *pDb, int eParam, ...){
  int rc = LSM_OK;
  va_list ap;
  va_start(ap, eParam);

  switch( eParam ){
    case LSM_CONFIG_AUTOFLUSH: {
      /* This parameter is read and written in KB. But all internal 
      ** processing is done in bytes.  */
      int *piVal = va_arg(ap, int *);
      int iVal = *piVal;
      if( iVal>=0 && iVal<=(1024*1024) ){
        pDb->nTreeLimit = iVal*1024;
      }
      *piVal = (pDb->nTreeLimit / 1024);
      break;
    }

    case LSM_CONFIG_AUTOWORK: {
      int *piVal = va_arg(ap, int *);
      if( *piVal>=0 ){
        pDb->bAutowork = *piVal;
      }
      *piVal = pDb->bAutowork;
      break;
    }

    case LSM_CONFIG_AUTOCHECKPOINT: {
      /* This parameter is read and written in KB. But all internal processing
      ** (including the lsm_db.nAutockpt variable) is done in bytes.  */
      int *piVal = va_arg(ap, int *);
      if( *piVal>=0 ){
        int iVal = *piVal;
        pDb->nAutockpt = (i64)iVal * 1024;
      }
      *piVal = (int)(pDb->nAutockpt / 1024);









      break;
    }

    case LSM_CONFIG_PAGE_SIZE: {
      int *piVal = va_arg(ap, int *);
      if( pDb->pDatabase ){
        /* If lsm_open() has been called, this is a read-only parameter. 

          *piVal = pDb->nDfltPgsz;
        }
      }
      break;
    }

    case LSM_CONFIG_BLOCK_SIZE: {
      /* This parameter is read and written in KB. But all internal 
      ** processing is done in bytes.  */
      int *piVal = va_arg(ap, int *);
      if( pDb->pDatabase ){
        /* If lsm_open() has been called, this is a read-only parameter. 
        ** Set the output variable to the block-size in KB according to the 
        ** FileSystem object.  */
        *piVal = lsmFsBlockSize(pDb->pFS) / 1024;
      }else{
        int iVal = *piVal;
        if( iVal>=64 && iVal<=65536 && ((iVal-1) & iVal)==0 ){
          pDb->nDfltBlksz = iVal * 1024;
        }else{
          *piVal = pDb->nDfltBlksz / 1024;
        }
      }
      break;
    }

    case LSM_CONFIG_SAFETY: {
      int *piVal = va_arg(ap, int *);

<h1 id=using_lsm_in_applications>2. Using LSM in Applications </h1>

<p>LSM is not currently built or distributed independently. Instead, it
is part of the SQLite4 library. To use LSM in an application, the application
links against libsqlite4 and includes the header file "lsm.h" in any files
that access the LSM API.

<p><span style=color:red>Pointer to build instructions for sqlite4</span>

<h1 id=basic_usage>3. Basic Usage</h1>

<h2 id=opening_and_closing_database_connections>3.1. Opening and Closing Database Connections </h2>

<p>Opening a connection to a database is a two-step process. The 
<a href=lsmapi.wiki#lsm_new>lsm_new()</a> function is used to create a new

    this option is set to the number of segments that the library attempts 
    to merge simultaneously. Increasing this value may reduce the total
    amount of data written to the database file. Decreasing it increases
    the amount of data written to the file, but also decreases the average
    number of segments present in the file, which can improve the performance
    of database read operations.

    <p>Additionally, whether or not auto-work is enabled, this option is used
    to determine the maximum number of segments of a given age that are 
    allowed to accumulate in the database file. This is described in the
    <a href=#compulsary_work_and_checkpoints>compulsary work and checkpoints</a>
    section below.

    <p>The default value is 4. This option must be set to a value between
    2 and 8, inclusive.

  <dt> <a href=lsmapi.wiki#LSM_CONFIG_AUTOWORK>LSM_CONFIG_AUTOWORK</a>
  <dd> <p style=margin-top:0>
    <p>This option may be set to either 1 (true) or 0 (false). If it is set
    to true, then work and checkpoint operations are automatically scheduled
    within calls to lsm_insert(), lsm_delete(), lsm_delete_range() and
    lsm_commit(). Otherwise, if it is set to false, these operations must
    be <a href=#explicit_scheduling>explicitly scheduled</a> by the
    application. 


    <p>The default value is 1.

  <dt> <a href=lsmapi.wiki#LSM_CONFIG_MMAP>LSM_CONFIG_MMAP</a>
  <dd> <p style=margin-top:0>
    If LSM is running on a system with a 64-bit address space, this option
    may be set to either 1 (true) or 0 (false). On a 32-bit platform, it is