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Diffstat (limited to 'db2/log/log_put.c')
-rw-r--r--db2/log/log_put.c210
1 files changed, 121 insertions, 89 deletions
diff --git a/db2/log/log_put.c b/db2/log/log_put.c
index 225595f33e..92d9563301 100644
--- a/db2/log/log_put.c
+++ b/db2/log/log_put.c
@@ -7,7 +7,7 @@
#include "config.h"
#ifndef lint
-static const char sccsid[] = "@(#)log_put.c 10.14 (Sleepycat) 9/23/97";
+static const char sccsid[] = "@(#)log_put.c 10.20 (Sleepycat) 11/2/97";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
@@ -29,9 +29,10 @@ static const char sccsid[] = "@(#)log_put.c 10.14 (Sleepycat) 9/23/97";
#include "common_ext.h"
static int __log_fill __P((DB_LOG *, void *, u_int32_t));
+static int __log_flush __P((DB_LOG *, const DB_LSN *));
static int __log_newfd __P((DB_LOG *));
-static int __log_write __P((DB_LOG *, void *, u_int32_t));
static int __log_putr __P((DB_LOG *, const DBT *, u_int32_t));
+static int __log_write __P((DB_LOG *, void *, u_int32_t));
/*
* log_put --
@@ -63,11 +64,8 @@ log_put(dblp, lsn, dbt, flags)
}
LOCK_LOGREGION(dblp);
-
ret = __log_put(dblp, lsn, dbt, flags);
-
UNLOCK_LOGREGION(dblp);
-
return (ret);
}
@@ -102,14 +100,10 @@ __log_put(dblp, lsn, dbt, flags)
"log_put: record larger than maximum file size");
return (EINVAL);
}
- if (lp->b_off != 0) {
- if ((ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
- return (ret);
- if ((ret = __db_fsync(dblp->lfd)) != 0)
- return (ret);
- lp->s_lsn.file = lp->lsn.file;
- lp->s_lsn.offset = lp->lsn.offset - 1;
- }
+
+ /* Flush the log. */
+ if ((ret = __log_flush(dblp, NULL)) != 0)
+ return (ret);
/*
* Save the last known offset from the previous file, we'll
@@ -117,9 +111,15 @@ __log_put(dblp, lsn, dbt, flags)
*/
lastoff = lp->lsn.offset;
+ /* Point the current LSN to the new file. */
++lp->lsn.file;
lp->lsn.offset = 0;
+
+ /* Reset the file write offset. */
lp->w_off = 0;
+
+ /* Reset the first-unwritten LSN for the buffer. */
+ lp->uw_lsn = lp->lsn;
} else
lastoff = 0;
@@ -149,56 +149,54 @@ __log_put(dblp, lsn, dbt, flags)
* Put out the checkpoint record (above).
* Save the LSN of the checkpoint in the shared region.
* Append the set of file name information into the log.
- * Flush the current buffer contents to disk.
- * Sync the log to disk.
- * Save the time the checkpoint was written.
- * Reset the bytes written since the last checkpoint.
*/
if (flags == DB_CHECKPOINT) {
lp->c_lsn = *lsn;
for (fnp = SH_TAILQ_FIRST(&dblp->lp->fq, __fname);
fnp != NULL; fnp = SH_TAILQ_NEXT(fnp, q, __fname)) {
- t.data = ADDR(dblp, fnp->name_off);
+ t.data = R_ADDR(dblp, fnp->name_off);
t.size = strlen(t.data) + 1;
memset(&fid_dbt, 0, sizeof(fid_dbt));
- fid_dbt.data = ADDR(dblp, fnp->fileid_off);
+ fid_dbt.data = R_ADDR(dblp, fnp->fileid_off);
fid_dbt.size = DB_FILE_ID_LEN;
if ((ret = __log_register_log(dblp, NULL, &r_unused,
0, &t, &fid_dbt, fnp->id, fnp->s_type)) != 0)
return (ret);
}
- if (lp->b_off != 0 &&
- (ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
- return (ret);
- (void)time(&lp->chkpt);
- lp->written = 0;
-
- if ((ret = __db_fsync(dblp->lfd)) != 0)
- return (ret);
- lp->s_lsn.file = lp->lsn.file;
- lp->s_lsn.offset = lp->lsn.offset - 1;
}
- /* We always flush on a checkpoint. */
- if (flags == DB_FLUSH || flags == DB_CHECKPOINT) {
- if (lp->b_off != 0 &&
- (ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
+ /*
+ * On a checkpoint or when flush is requested, we:
+ * Flush the current buffer contents to disk.
+ * Sync the log to disk.
+ */
+ if (flags == DB_FLUSH || flags == DB_CHECKPOINT)
+ if ((ret = __log_flush(dblp, NULL)) != 0)
return (ret);
- if ((ret = __db_fsync(dblp->lfd)) != 0)
- return (ret);
- lp->s_lsn.file = lp->lsn.file;
- lp->s_lsn.offset = lp->lsn.offset - 1;
+ /*
+ * On a checkpoint, we:
+ * Save the time the checkpoint was written.
+ * Reset the bytes written since the last checkpoint.
+ */
+ if (flags == DB_CHECKPOINT) {
+ (void)time(&lp->chkpt);
+ lp->stat.st_wc_bytes = lp->stat.st_wc_mbytes = 0;
}
/*
- * If we just did I/O, i.e., this LSN could have spanned the start of
- * the in-core buffer, we remember it so that we can flush correctly
- * during a sync.
+ * When an application calls the log_flush routine, we need to figure
+ * out if the current buffer needs to be flushed. The problem is that
+ * if a record spans buffers, it's possible for the record continued
+ * in the current buffer to have begun in a previous buffer. Each time
+ * we write a buffer, we update the first-unwritten LSN to point to the
+ * first LSN after that written buffer. If we have a spanning record,
+ * correct that value to be the LSN that started it all, here.
*/
if (lsn->offset < lp->w_off && lsn->offset + lp->len > lp->w_off)
- lp->span_lsn = *lsn;
+ lp->uw_lsn = *lsn;
+
return (0);
}
@@ -248,6 +246,24 @@ log_flush(dblp, lsn)
DB_LOG *dblp;
const DB_LSN *lsn;
{
+ int ret;
+
+ LOCK_LOGREGION(dblp);
+ ret = __log_flush(dblp, lsn);
+ UNLOCK_LOGREGION(dblp);
+ return (ret);
+}
+
+/*
+ * __log_flush --
+ * Write all records less than or equal to the specified LSN; internal
+ * version.
+ */
+static int
+__log_flush(dblp, lsn)
+ DB_LOG *dblp;
+ const DB_LSN *lsn;
+{
DB_LSN t_lsn;
LOG *lp;
int ret;
@@ -255,60 +271,64 @@ log_flush(dblp, lsn)
ret = 0;
lp = dblp->lp;
- LOCK_LOGREGION(dblp);
-
- /* If no LSN specified, flush the entire log. */
+ /*
+ * If no LSN specified, flush the entire log by setting the flush LSN
+ * to the last LSN written in the log. Otherwise, check that the LSN
+ * isn't a non-existent record for the log.
+ */
if (lsn == NULL) {
t_lsn.file = lp->lsn.file;
t_lsn.offset = lp->lsn.offset - lp->len;
lsn = &t_lsn;
- }
-
- /* If it's a non-existent record, it's an error. */
- if (lsn->file > lp->lsn.file ||
- (lsn->file == lp->lsn.file && lsn->offset > lp->lsn.offset)) {
- __db_err(dblp->dbenv, "log_flush: LSN past current end-of-log");
- ret = EINVAL;
- goto ret1;
- }
-
- /*
- * If it's from a previous file, we're done because we sync each
- * file when we move to a new one.
- */
- if (lsn->file < lp->lsn.file)
- goto ret1;
+ } else
+ if (lsn->file > lp->lsn.file ||
+ (lsn->file == lp->lsn.file &&
+ lsn->offset > lp->lsn.offset - lp->len)) {
+ __db_err(dblp->dbenv,
+ "log_flush: LSN past current end-of-log");
+ return (EINVAL);
+ }
/*
- * If it's less than the last-sync'd offset, we've already sync'd
- * this LSN.
+ * If the LSN is less than the last-sync'd LSN, we're done. Note,
+ * the last-sync LSN saved in s_lsn is the LSN of the first byte
+ * that has not yet been written to disk, so the test is <, not <=.
*/
- if (lsn->offset <= lp->s_lsn.offset)
- goto ret1;
+ if (lsn->file < lp->s_lsn.file ||
+ (lsn->file == lp->s_lsn.file && lsn->offset < lp->s_lsn.offset))
+ return (0);
/*
* We may need to write the current buffer. We have to write the
- * current buffer if the sync LSN is greater than or equal to the
- * saved spanning-LSN.
+ * current buffer if the flush LSN is greater than or equal to the
+ * first-unwritten LSN (uw_lsn). If we write the buffer, then we
+ * update the first-unwritten LSN.
*/
- if (lsn->file >= lp->span_lsn.file &&
- lsn->offset >= lp->span_lsn.offset)
+ if (lp->b_off != 0 &&
+ lsn->file >= lp->uw_lsn.file && lsn->offset >= lp->uw_lsn.offset)
if ((ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
- goto ret1;
+ return (ret);
- /* Acquire a file descriptor if we don't have one. */
- if (dblp->lfname != dblp->lp->lsn.file &&
- (ret = __log_newfd(dblp)) != 0)
- goto ret1;
+ /*
+ * It's possible that this thread may never have written to this log
+ * file. Acquire a file descriptor if we don't already have one.
+ */
+ if (dblp->lfname != dblp->lp->lsn.file)
+ if ((ret = __log_newfd(dblp)) != 0)
+ return (ret);
+ /* Sync all writes to disk. */
if ((ret = __db_fsync(dblp->lfd)) != 0)
- goto ret1;
+ return (ret);
+ ++lp->stat.st_scount;
- lp->s_lsn.file = lp->lsn.file;
- lp->s_lsn.offset = lsn->offset;
+ /*
+ * Set the last-synced LSN, the first LSN after the last record
+ * that we know is on disk.
+ */
+ lp->s_lsn = lp->uw_lsn;
-ret1: UNLOCK_LOGREGION(dblp);
- return (ret);
+ return (0);
}
/*
@@ -385,17 +405,32 @@ __log_write(dblp, addr, len)
* Seek to the offset in the file (someone may have written it
* since we last did).
*/
- if ((ret = __db_lseek(dblp->lfd, 0, 0, lp->w_off, SEEK_SET)) != 0)
+ if ((ret = __db_seek(dblp->lfd, 0, 0, lp->w_off, SEEK_SET)) != 0)
return (ret);
if ((ret = __db_write(dblp->lfd, addr, len, &nw)) != 0)
return (ret);
if (nw != (int32_t)len)
return (EIO);
- /* Update the seek offset and reset the buffer offset. */
+ /*
+ * Reset the buffer offset, update the seek offset, and update the
+ * first-unwritten LSN.
+ */
lp->b_off = 0;
lp->w_off += len;
- lp->written += len;
+ lp->uw_lsn.file = lp->lsn.file;
+ lp->uw_lsn.offset = lp->w_off;
+
+ /* Update written statistics. */
+ if ((lp->stat.st_w_bytes += len) >= MEGABYTE) {
+ lp->stat.st_w_bytes -= MEGABYTE;
+ ++lp->stat.st_w_mbytes;
+ }
+ if ((lp->stat.st_wc_bytes += len) >= MEGABYTE) {
+ lp->stat.st_wc_bytes -= MEGABYTE;
+ ++lp->stat.st_wc_mbytes;
+ }
+ ++lp->stat.st_wcount;
return (0);
}
@@ -415,11 +450,8 @@ log_file(dblp, lsn, namep, len)
char *p;
LOCK_LOGREGION(dblp);
-
ret = __log_name(dblp, lsn->file, &p);
-
UNLOCK_LOGREGION(dblp);
-
if (ret != 0)
return (ret);
@@ -429,7 +461,7 @@ log_file(dblp, lsn, namep, len)
return (ENOMEM);
}
(void)strcpy(namep, p);
- free(p);
+ __db_free(p);
return (0);
}
@@ -455,7 +487,7 @@ __log_newfd(dblp)
dblp->lfname = dblp->lp->lsn.file;
if ((ret = __log_name(dblp, dblp->lfname, &p)) != 0)
return (ret);
- if ((ret = __db_fdopen(p,
+ if ((ret = __db_open(p,
DB_CREATE | DB_SEQUENTIAL,
DB_CREATE | DB_SEQUENTIAL,
dblp->lp->persist.mode, &dblp->lfd)) != 0)
@@ -472,14 +504,14 @@ __log_newfd(dblp)
* PUBLIC: int __log_name __P((DB_LOG *, int, char **));
*/
int
-__log_name(dblp, fileno, namep)
+__log_name(dblp, filenumber, namep)
DB_LOG *dblp;
char **namep;
- int fileno;
+ int filenumber;
{
char name[sizeof(LFNAME) + 10];
- (void)snprintf(name, sizeof(name), LFNAME, fileno);
+ (void)snprintf(name, sizeof(name), LFNAME, filenumber);
return (__db_appname(dblp->dbenv,
DB_APP_LOG, dblp->dir, name, NULL, namep));
}