diff options
author | Ulrich Drepper <drepper@redhat.com> | 1997-11-12 00:06:02 +0000 |
---|---|---|
committer | Ulrich Drepper <drepper@redhat.com> | 1997-11-12 00:06:02 +0000 |
commit | cc3fa755128c70f8afc2d604936f33e4d7d652d8 (patch) | |
tree | 0c68c1298140e1524078e8bfdf5154fb6129b680 /db2/mp/mp_sync.c | |
parent | 86187531d302de284b67ac162cf76c60c86bd7da (diff) | |
download | glibc-cc3fa755128c70f8afc2d604936f33e4d7d652d8.tar.gz glibc-cc3fa755128c70f8afc2d604936f33e4d7d652d8.tar.xz glibc-cc3fa755128c70f8afc2d604936f33e4d7d652d8.zip |
Update. cvs/libc-ud-971111
1997-11-11 21:30 Ulrich Drepper <drepper@cygnus.com> * include/sys/stat.h: Define stat, fstat, lstat and *64 variants as macros so the the library compiles correctly even without optimization. * io/fstat.c: Undef fstat. * io/fstat64.c: Undef fstat64 * io/lstat.c: Undef lstat. * io/lstat64.c: Undef lstat64 * io/stat.c: Undef stat. * io/stat64.c: Undef stat64 * io/fts.c: Include <include/sys/stat.h> to get macro definitions. * io/ftw.c: Likewise. * io/getdirname.c: Likewise. * Makefile (install): Run test-installation.pl if possible. * db2/Makefile: Update from db-2.3.12. * db2/db.h: Likewise. * db2/db_int.h: Likewise. * db2/btree/bt_cursor.c: Likewise. * db2/btree/bt_delete.c: Likewise. * db2/btree/bt_open.c: Likewise. * db2/btree/bt_put.c: Likewise. * db2/btree/bt_rec.c: Likewise. * db2/btree/bt_recno.c: Likewise. * db2/btree/bt_search.c: Likewise. * db2/btree/bt_split.c: Likewise. * db2/btree/bt_stat.c: Likewise. * db2/btree/btree.src: Likewise. * db2/btree/btree_auto.c: Likewise. * db2/btree/bt_cursor.c: Likewise. * db2/btree/bt_delete.c: Likewise. * db2/btree/bt_open.c: Likewise. * db2/btree/bt_put.c: Likewise. * db2/btree/bt_rec.c: Likewise. * db2/btree/bt_recno.c: Likewise. * db2/btree/bt_search.c: Likewise. * db2/btree/bt_split.c: Likewise. * db2/btree/bt_stat.c: Likewise. * db2/btree/btree.src: Likewise. * db2/btree/btree_auto.c: Likewise. * db2/common/db_appinit.c: Likewise. * db2/common/db_apprec.c: Likewise. * db2/common/db_byteorder.c: Likewise. * db2/common/db_region.c: Likewise. * db2/db/db.c: Likewise * db2/db/db.src: Likewise * db2/db/db_auto.c: Likewise * db2/db/db_dispatch.c: Likewise * db2/db/db_dup.c: Likewise * db2/db/db_overflow.c: Likewise * db2/db/db_pr.c: Likewise * db2/db/db_rec.c: Likewise * db2/db/db_ret.c: Likewise * db2/db/db_thread.c: Likewise * db2/db185/db185.c: Likewise. * db2/hash/hash.c: Likewise. * db2/hash/hash.src: Likewise. * db2/hash/hash_auto.c: Likewise. * db2/hash/hash_dup.c: Likewise. * db2/hash/hash_page.c: Likewise. * db2/hash/hash_rec.c: Likewise. * db2/include/btree_auto.h: Likewise. * db2/include/btree_ext.h: Likewise. * db2/include/clib_ext.h: Likewise. * db2/include/common_ext.h: Likewise. * db2/include/db.h.src: Likewise. * db2/include/db_am.h: Likewise. * db2/include/db_auto.h: Likewise. * db2/include/db_cxx.h: Likewise. * db2/include/db_ext.h: Likewise. * db2/include/db_int.h.src: Likewise. * db2/include/hash.h: Likewise. * db2/include/hash_auto.h: Likewise. * db2/include/hash_ext.h: Likewise. * db2/include/lock.h: Likewise. * db2/include/lock_ext.h: Likewise. * db2/include/log.h: Likewise. * db2/include/log_ext.h: Likewise. * db2/include/mp.h: Likewise. * db2/include/mp_ext.h: Likewise. * db2/include/mutex_ext.h: Likewise. * db2/include/os_ext.h: Likewise. * db2/include/os_func.h: Likewise. * db2/include/txn.h: Likewise. * db2/include/txn_ext.h: Likewise. * db2/lock/lock.c: Likewise. * db2/lock/lock_deadlock.c: Likewise. * db2/log/log.c: Likewise. * db2/log/log_archive.c: Likewise. * db2/log/log_auto.c: Likewise. * db2/log/log_findckp.c: Likewise. * db2/log/log_get.c: Likewise. * db2/log/log_put.c: Likewise. * db2/log/log_rec.c: Likewise. * db2/log/log_register.c: Likewise. * db2/mp/mp_bh.c: Likewise. * db2/mp/mp_fget.c: Likewise. * db2/mp/mp_fopen.c: Likewise. * db2/mp/mp_fput.c: Likewise. * db2/mp/mp_fset.c: Likewise. * db2/mp/mp_open.c: Likewise. * db2/mp/mp_pr.c: Likewise. * db2/mp/mp_region.c: Likewise. * db2/mp/mp_sync.c: Likewise. * db2/mutex/mutex.c: Likewise. * db2/os/os_abs.c: Likewise. * db2/os/os_dir.c: Likewise. * db2/os/os_fid.c: Likewise. * db2/os/os_fsync.c: Likewise. * db2/os/os_func.c: Likewise. * db2/os/os_map.c: Likewise. * db2/os/os_oflags.c: Likewise. * db2/os/os_open.c: Likewise. * db2/os/os_rpath.c: Likewise. * db2/os/os_rw.c: Likewise. * db2/os/os_seek.c: Likewise. * db2/os/os_sleep.c: Likewise. * db2/os/os_stat.c: Likewise. * db2/os/os_unlink.c: Likewise. * db2/progs/db_deadlock/db_deadlock.c: Likewise. * db2/progs/db_dump/db_dump.c: Likewise. * db2/progs/db_load/db_load.c: Likewise. * db2/progs/db_recover/db_recover.c: Likewise. * db2/progs/db_stat/db_stat.c: Likewise. * db2/txn/txn.c: Likewise. * db2/txn/txn_auto.c: Likewise. * db2/txn/txn_rec.c: Likewise. * db2/os/db_os_abs.c: Removed. * db2/os/db_os_dir.c: Removed. * db2/os/db_os_fid.c: Removed. * db2/os/db_os_lseek.c: Removed. * db2/os/db_os_mmap.c: Removed. * db2/os/db_os_open.c: Removed. * db2/os/db_os_rw.c: Removed. * db2/os/db_os_sleep.c: Removed. * db2/os/db_os_stat.c: Removed. * db2/os/db_os_unlink.c: Removed. * libio/stdio.h (fopen): Add __restrict to parameters. * manual/process.texi (system): Describe behaviour for NULL argument. * stdio-common/printf-parse.h: Parse hh modifier. * stdio-common/vfprintf.c: Handle hh modifier. * stdio-common/vfscanf.c: Likewise. * manual/stdio.texi: Describe hh modifier for scanf/printf. * math/complex.h: Don't define _Imaginary_I, but instead _Complex_I. gcc does no yet know the `imaginary' keyword. * math/test-math.c: Add little test for know gcc bug. * math/tgmath.h: Make complex versions of log10() only available if __USE_GNU. * stdlib/test-canon.c: Fix typo. * sysdeps/generic/setenv.c: Avoid compilation warnings. Reported by Jim Meyering. * sysdeps/generic/bits/errno.h: EILSEQ is an ISO C error number. * sysdeps/mach/hurd/bits/errno.h: Likewise. * sysdeps/standalone/bits/errno.h: Likewise. * sysdeps/unix/sysv/linux/bits/errno.h: Likewise. * sysdeps/i386/i586/memcpy.S: New file. * sysdeps/i386/i586/mempcpy.S: New file. * sysdeps/i386/i586/memset.S: Fix typo. * sysdeps/posix/getcwd.c: Define HAVE_MEMPCPY for _LIBC. Add casts. * sysdeps/posix/system.c: Add comment to explain code. * sysdeps/wordsize-32/inttypes.h: Include <stddef.h> for wchar_t. Define PTRDIFF_{MIN,MAX}, SIG_ATOMIC_{MIN,MAX}, SIZE_MAX, WCHAR_{MIN,MAX}, WINT_{MIN,MAX}. Define wcstoimax, wcstoumax. * sysdeps/wordsize-64/inttypes.h: Likewise. * wcsmbs/wchar.h: Define WCHAR_{MIN,MAX} if not already defined. Declare __wcsto{l,ul,ll,ull}_internal only if not already done. * time/Makefile (routines): Add strfxtime. * time/strftime.c: Implement %F and %f format. * time/strfxtime.c: New file. * time/time.h: Define new types and symbols from ISO C 9X. * time/mktime.c: Little comment correction. 1997-11-10 Andreas Jaeger <aj@arthur.rhein-neckar.de> * sysdeps/libm-ieee754/s_sincosl.c: Fix typo. * sysdeps/libm-ieee754/s_tanl.c: Fix typo. * sysdeps/libm-ieee754/s_floorl.c: Correct typos. * sysdeps/libm-ieee754/e_remainderl.c: Replace EXTRACT_LDOUBLE_WORDS by GET_LDOUBLE_WORDS. * sysdeps/libm-ieee754/e_atan2l.c: Replace EXTRACT_LDOUBLE_WORDS by GET_LDOUBLE_WORDS. * sysdeps/libm-ieee754/s_scalbnl.c: Replace ";" by "," for correct variable declaration. * sysdeps/libm-ieee754/s_scalblnl.c: Likewise. * sysdeps/libm-ieee754/s_lrint.c (__lrint): Correct function. * math/libm-test.c (sqrt_test): Add test for sqrt (0.25). (asin_test): Add more test. 1997-11-10 23:34 Ulrich Drepper <drepper@cygnus.com> * sysdeps/libm-ieee754/e_asin.c: Add braces to make code clearer and to not confuse the poor compiler. * sysdeps/libm-ieee754/e_asinf.c: Likewise. Reported by vertex@cagent.com. 1997-11-09 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * elf/dl-lookup.c (do_lookup): Don't accept the base version if we require a specific one. * libio/oldfreopen.c: Bind old symbols to version GLIBC_2.0. * libio/oldiofopen.c: Likewise. * libio/oldstdfiles.c: Likewise. * libc.map: Export them. 1997-11-10 07:40 H.J. Lu <hjl@gnu.ai.mit.edu> * stdlib/exit.c (exit): Handle recursive calls to exit (). 1997-11-09 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/m68k/fpu/s_llrint.c: Fixed to take double argument instead of long double. * sysdeps/m68k/fpu/s_llrintf.c: New file. * sysdeps/m68k/fpu/s_llrintl.c: New file. * sysdeps/libm-ieee754/s_llrint.c: Make compilable and fix overflow condition. * sysdeps/libm-ieee754/s_llrintf.c: Fix overflow condition. * sysdeps/libm-ieee754/s_llrintl.c: Likewise. * sysdeps/libm-ieee754/s_llround.c: Likewise. * sysdeps/libm-ieee754/s_llroundf.c: Likewise. * sysdeps/libm-ieee754/s_llroundl.c: Likewise. * sysdeps/libm-ieee754/s_lrint.c: Likewise. * sysdeps/libm-ieee754/s_lrintf.c: Likewise. * sysdeps/libm-ieee754/s_lrintl.c: Likewise. * sysdeps/libm-ieee754/s_lround.c: Likewise. * sysdeps/libm-ieee754/s_lroundf.c: Likewise. * sysdeps/libm-ieee754/s_lroundl.c: Likewise. * math/libm-test.c: Test all three variants of lrint and llrint. Fix typos in lround and llround tests. Add tests for boundary cases for lrint and llround. 1997-11-08 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * manual/arith.texi: Misc doc fixes. * manual/ctype.texi: Likewise. * manual/pattern.texi: Likewise. * manual/terminal.texi: Likewise. 1997-11-08 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/unix/sysv/linux/xstatconv.c: Use struct assignment instead of memcpy to let the compiler use whatever it regards as optimal. * sysdeps/unix/sysv/linux/alpha/xstatconv.c: Likewise. 1997-11-08 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/unix/sysv/linux/Makefile (sysdep_headers) [$(subdir)=misc]: Add sys/prctl.h. * sysdeps/unix/sysv/linux/Dist: Distribute it. 1997-11-08 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * io/ftwtest-sh: Don't use the unknown which command, instead try pwd as /bin/pwd and /usr/bin/pwd. 1997-11-08 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * manual/maint.texi (Tools for Installation): Don't recommend broken version 3.76.1 of make. (Porting): Fix wording. 1997-11-06 06:13 H.J. Lu <hjl@gnu.ai.mit.edu> * config.make.in (build-pic-default): New, defined with pic_default. * configure.in (pic_default): New, set to yes if PIC is default. * Makeconfig (CPPFLAGS-.o, CPPFLAGS-.op, CPPFLAGS-.og, CPPFLAGS-.ob): Add -DPIC if $(build-pic-default) is yes. 1997-11-09 18:15 Ulrich Drepper <drepper@cygnus.com> * Makerules (libc.so): Fix typo. * csu/Makefile (CFLAGS-initfini.s): Correctly fix moving function definition. Patch by Zack Weinberg <zack@rabi.phys.columbia.edu>. * stdlib/strtod.c: Handle numbers like 0.0e10000 correctly which produce ±0.0. Reported by Joe Keane <jgk@jgk.org>. * sysdeps/libm-ieee754/s_ceill.c: Fix typos. * sysdeps/libm-ieee754/s_llrint.c: Correct code, it never worked. 1997-11-06 07:00 H.J. Lu <hjl@gnu.ai.mit.edu> * sysdeps/unix/sysv/i386/i686/time.S: Removed. 1997-11-08 14:07 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> * nis/libnsl.map: Add __do_niscall2 for nis_cachemgr. * nis/nis_call.c: Set UDP resend timeout correct. * nis/nss_compat/compat-grp.c: Rewritten to make it faster. * nis/nss_compat/compat-pwd.c: Likewise. * nis/nss_compat/compat-spwd.c: Likewise. * nis/ypclnt.c: Fix UDP resend timeout, fix yp_bind/do_ypcall interaction. * inet/protocols/routed.h: Include sys/socket.h. * inet/protocols/talkd.h: Likewise. * inet/protocols/timed.h: Include rpc/types.h. * sunrpc/rpc/pmap_clnt.h: Include rpc/clnt.h. 1997-11-06 01:39 Ulrich Drepper <drepper@cygnus.com> * Makerules (libc.so): Add missing closing brace. 1997-11-05 Brendan Kehoe <brendan@lisa.cygnus.com> * libio.h (__P): Name its arg `p' instead of `params'. This was added solely to work around problems with the definition of __P in the Solaris math.h header.
Diffstat (limited to 'db2/mp/mp_sync.c')
-rw-r--r-- | db2/mp/mp_sync.c | 393 |
1 files changed, 320 insertions, 73 deletions
diff --git a/db2/mp/mp_sync.c b/db2/mp/mp_sync.c index 65b2a18267..2f042df9e1 100644 --- a/db2/mp/mp_sync.c +++ b/db2/mp/mp_sync.c @@ -7,13 +7,14 @@ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)mp_sync.c 10.9 (Sleepycat) 8/29/97"; +static const char sccsid[] = "@(#)mp_sync.c 10.15 (Sleepycat) 11/1/97"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES #include <sys/types.h> #include <errno.h> +#include <stdlib.h> #include <string.h> #endif @@ -23,6 +24,8 @@ static const char sccsid[] = "@(#)mp_sync.c 10.9 (Sleepycat) 8/29/97"; #include "mp.h" #include "common_ext.h" +static int __bhcmp __P((const void *, const void *)); + /* * memp_sync -- * Mpool sync function. @@ -32,27 +35,40 @@ memp_sync(dbmp, lsnp) DB_MPOOL *dbmp; DB_LSN *lsnp; { - BH *bhp; + BH *bhp, **bharray; DB_ENV *dbenv; MPOOL *mp; MPOOLFILE *mfp; - int can_write, wrote, lsn_cnt, restart, ret; + int ar_cnt, cnt, nalloc, next, notused, ret, wrote; dbenv = dbmp->dbenv; - if (dbmp->dbenv->lg_info == NULL) { - __db_err(dbenv, "memp_sync requires logging"); + if (dbenv->lg_info == NULL) { + __db_err(dbenv, "memp_sync: requires logging"); return (EINVAL); } + /* + * We try and write the buffers in page order so that the underlying + * filesystem doesn't have to seek and can write contiguous blocks, + * plus, we don't want to hold the region lock while we write the + * buffers. Get memory to hold the buffer pointers. Get a good-size + * block, too, because we realloc while holding the region lock if we + * run out. + */ + if ((bharray = + (BH **)__db_malloc((nalloc = 1024) * sizeof(BH *))) == NULL) + return (ENOMEM); + LOCKREGION(dbmp); /* - * If the application is asking about a previous call, and we haven't - * found any buffers that the application holding the pin couldn't - * write, return yes or no based on the current count. Note, if the - * application is asking about a LSN *smaller* than one we've already - * handled, then we return based on the count for that LSN. + * If the application is asking about a previous call to memp_sync(), + * and we haven't found any buffers that the application holding the + * pin couldn't write, return yes or no based on the current count. + * Note, if the application is asking about a LSN *smaller* than one + * we've already handled or are currently handling, then we return a + * result based on the count for the larger LSN. */ mp = dbmp->mp; if (!F_ISSET(mp, MP_LSN_RETRY) && log_compare(lsnp, &mp->lsn) <= 0) { @@ -61,9 +77,7 @@ memp_sync(dbmp, lsnp) ret = 0; } else ret = DB_INCOMPLETE; - - UNLOCKREGION(dbmp); - return (ret); + goto done; } /* Else, it's a new checkpoint. */ @@ -74,7 +88,7 @@ memp_sync(dbmp, lsnp) * for which we were already doing a checkpoint. (BTW, I don't expect * to see multiple LSN's from the same or multiple processes, but You * Just Never Know. Responding as if they all called with the largest - * of the LSNs specified makes everything work. + * of the LSNs specified makes everything work.) * * We don't currently use the LSN we save. We could potentially save * the last-written LSN in each buffer header and use it to determine @@ -93,64 +107,127 @@ memp_sync(dbmp, lsnp) /* * Walk the list of buffers and mark all dirty buffers to be written - * and all pinned buffers to be potentially written. We do this in - * single fell swoop while holding the region locked so that processes - * can't make new buffers dirty, causing us to never finish. Since - * the application may have restarted the sync, clear any BH_WRITE - * flags that appear to be left over. + * and all pinned buffers to be potentially written (we can't know if + * we'll need to write them until the holding process returns them to + * the cache). We do this in one pass while holding the region locked + * so that processes can't make new buffers dirty, causing us to never + * finish. Since the application may have restarted the sync, clear + * any BH_WRITE flags that appear to be left over from previous calls. + * + * Keep a count of the total number of buffers we need to write in + * MPOOL->lsn_cnt, and for each file, in MPOOLFILE->lsn_count. */ - can_write = lsn_cnt = 0; - for (lsn_cnt = 0, bhp = SH_TAILQ_FIRST(&mp->bhq, __bh); + ar_cnt = 0; + for (bhp = SH_TAILQ_FIRST(&mp->bhq, __bh); bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, q, __bh)) if (F_ISSET(bhp, BH_DIRTY) || bhp->ref != 0) { F_SET(bhp, BH_WRITE); - if (bhp->ref == 0) - can_write = 1; + ++mp->lsn_cnt; - mfp = ADDR(dbmp, bhp->mf_offset); + mfp = R_ADDR(dbmp, bhp->mf_offset); ++mfp->lsn_cnt; - ++lsn_cnt; + /* + * If the buffer isn't in use, we should be able to + * write it immediately, so save a reference to it. + */ + if (bhp->ref == 0) { + if (ar_cnt == nalloc) { + nalloc *= 2; + if ((bharray = + (BH **)__db_realloc(bharray, + nalloc * sizeof(BH *))) == NULL) { + ret = ENOMEM; + goto err; + } + } + bharray[ar_cnt++] = bhp; + } } else F_CLR(bhp, BH_WRITE); - mp->lsn_cnt = lsn_cnt; - - /* If there no buffers we can write, we're done. */ - if (!can_write) { - UNLOCKREGION(dbmp); - return (mp->lsn_cnt ? DB_INCOMPLETE : 0); + /* If there no buffers we can write immediately, we're done. */ + if (ar_cnt == 0) { + ret = mp->lsn_cnt ? DB_INCOMPLETE : 0; + goto done; } - /* - * Write any buffers that we can. Restart the walk after each write, - * __memp_pgwrite() discards and reacquires the region lock during I/O. - */ -retry: for (bhp = SH_TAILQ_FIRST(&mp->bhq, __bh); - bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, q, __bh)) { - /* Ignore pinned or locked buffers. */ - if (!F_ISSET(bhp, BH_WRITE) || - bhp->ref != 0 || F_ISSET(bhp, BH_LOCKED)) - continue; + /* Lock down the buffers and their contents. */ + for (cnt = 0; cnt < ar_cnt; ++cnt) + ++bharray[cnt]->ref; - mfp = ADDR(dbmp, bhp->mf_offset); - if ((ret = - __memp_bhwrite(dbmp, mfp, bhp, &restart, &wrote)) != 0) - goto err; - if (wrote) { - if (restart) - goto retry; + UNLOCKREGION(dbmp); + + /* Sort the buffers we're going to write. */ + qsort(bharray, ar_cnt, sizeof(BH *), __bhcmp); + + LOCKREGION(dbmp); + + /* Walk the array, writing buffers. */ + for (next = 0; next < ar_cnt; ++next) { + /* + * It's possible for a thread to have gotten the buffer since + * we listed it for writing. If the reference count is still + * 1, we're the only ones using the buffer, go ahead and write. + * If it's >1, then skip the buffer and assume that it will be + * written when it's returned to the cache. + */ + if (bharray[next]->ref > 1) { + --bharray[next]->ref; continue; } - __db_err(dbenv, "%s: unable to flush page: %lu", - ADDR(dbmp, mfp->path_off), (u_long)bhp->pgno); - ret = EPERM; - goto err; + + /* Write the buffer. */ + mfp = R_ADDR(dbmp, bharray[next]->mf_offset); + ret = + __memp_bhwrite(dbmp, mfp, bharray[next], ¬used, &wrote); + + /* Release the buffer. */ + --bharray[next]->ref; + + /* If there's an error, release the rest of the buffers. */ + if (ret != 0 || !wrote) { + while (++next < ar_cnt) + --bharray[next]->ref; + + if (ret != 0) + goto err; + + /* + * Any process syncing the shared memory buffer pool + * had better be able to write to any underlying file. + * Be understanding, but firm, on this point. + */ + if (!wrote) { + __db_err(dbenv, "%s: unable to flush page: %lu", + R_ADDR(dbmp, mfp->path_off), + (u_long)bharray[next]->pgno); + ret = EPERM; + goto err; + } + } } ret = mp->lsn_cnt ? DB_INCOMPLETE : 0; -err: UNLOCKREGION(dbmp); +done: + if (0) { +err: /* + * On error, clear: + * MPOOL->lsn_cnt (the total sync count) + * MPOOLFILE->lsn_cnt (the per-file sync count) + * BH_WRITE flag (the scheduled for writing flag) + */ + mp->lsn_cnt = 0; + for (mfp = SH_TAILQ_FIRST(&dbmp->mp->mpfq, __mpoolfile); + mfp != NULL; mfp = SH_TAILQ_NEXT(mfp, q, __mpoolfile)) + mfp->lsn_cnt = 0; + for (bhp = SH_TAILQ_FIRST(&mp->bhq, __bh); + bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, q, __bh)) + F_CLR(bhp, BH_WRITE); + } + UNLOCKREGION(dbmp); + __db_free(bharray); return (ret); } @@ -162,10 +239,10 @@ int memp_fsync(dbmfp) DB_MPOOLFILE *dbmfp; { - BH *bhp; + BH *bhp, **bharray; DB_MPOOL *dbmp; size_t mf_offset; - int pincnt, restart, ret, wrote; + int ar_cnt, cnt, nalloc, next, pincnt, notused, ret, wrote; /* * If this handle doesn't have a file descriptor that's open for @@ -175,35 +252,205 @@ memp_fsync(dbmfp) if (F_ISSET(dbmfp, MP_READONLY | MP_PATH_TEMP)) return (0); - dbmp = dbmfp->dbmp; ret = 0; + dbmp = dbmfp->dbmp; + mf_offset = R_OFFSET(dbmp, dbmfp->mfp); - mf_offset = OFFSET(dbmp, dbmfp->mfp); + /* + * We try and write the buffers in page order so that the underlying + * filesystem doesn't have to seek and can write contiguous blocks, + * plus, we don't want to hold the region lock while we write the + * buffers. Get memory to hold the buffer pointers. Get a good-size + * block, too, because we realloc while holding the region lock if we + * run out. + */ + nalloc = 1024; + if ((bharray = + (BH **)__db_malloc((size_t)nalloc * sizeof(BH *))) == NULL) + return (ENOMEM); LOCKREGION(dbmp); /* - * Walk the list of buffer headers for the MPOOLFILE, and write out any - * dirty buffers that we can. + * Walk the LRU list of buffer headers, and get a list of buffers to + * write for this MPOOLFILE. */ -retry: pincnt = 0; + ar_cnt = pincnt = 0; for (bhp = SH_TAILQ_FIRST(&dbmp->mp->bhq, __bh); - bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, q, __bh)) - if (F_ISSET(bhp, BH_DIRTY) && bhp->mf_offset == mf_offset) { - if (bhp->ref != 0 || F_ISSET(bhp, BH_LOCKED)) { - ++pincnt; - continue; - } - if ((ret = - __memp_pgwrite(dbmfp, bhp, &restart, &wrote)) != 0) + bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, q, __bh)) { + if (!F_ISSET(bhp, BH_DIRTY) || bhp->mf_offset != mf_offset) + continue; + if (bhp->ref != 0 || F_ISSET(bhp, BH_LOCKED)) { + ++pincnt; + continue; + } + + if (ar_cnt == nalloc) { + nalloc *= 2; + if ((bharray = (BH **)__db_realloc(bharray, + nalloc * sizeof(BH *))) == NULL) { + ret = ENOMEM; goto err; - if (!wrote) - ++pincnt; - if (restart) - goto retry; + } + } + + bharray[ar_cnt++] = bhp; + } + + /* Lock down the buffers and their contents. */ + for (cnt = 0; cnt < ar_cnt; ++cnt) + ++bharray[cnt]->ref; + + UNLOCKREGION(dbmp); + + /* Sort the buffers we're going to write. */ + qsort(bharray, ar_cnt, sizeof(BH *), __bhcmp); + + LOCKREGION(dbmp); + + /* Walk the array, writing buffers. */ + for (next = 0; next < ar_cnt; ++next) { + /* + * It's possible for a thread to have gotten the buffer since + * we listed it for writing. If the reference count is still + * 1, we're the only ones using the buffer, go ahead and write. + * If it's >1, then skip the buffer and assume that it will be + * written when it's returned to the cache. + */ + if (bharray[next]->ref > 1) { + ++pincnt; + + --bharray[next]->ref; + continue; } + /* Write the buffer. */ + ret = __memp_pgwrite(dbmfp, bharray[next], ¬used, &wrote); + + /* Release the buffer. */ + --bharray[next]->ref; + + /* If there's an error, release the rest of the buffers. */ + if (ret != 0) { + while (++next < ar_cnt) + --bharray[next]->ref; + goto err; + } + if (!wrote) + ++pincnt; + } + +err: UNLOCKREGION(dbmp); + + __db_free(bharray); + + /* + * Sync the underlying file as the last thing we do, so that the OS + * has maximal opportunity to flush buffers before we request it. + * + * XXX: + * Don't lock the region around the sync, fsync(2) has no atomicity + * issues. + */ + if (ret == 0) + return (pincnt == 0 ? __db_fsync(dbmfp->fd) : DB_INCOMPLETE); + return (ret); + +} + +/* + * memp_trickle -- + * Keep a specified percentage of the buffers clean. + */ +int +memp_trickle(dbmp, pct, nwrotep) + DB_MPOOL *dbmp; + int pct, *nwrotep; +{ + BH *bhp; + MPOOL *mp; + MPOOLFILE *mfp; + u_long total; + int notused, ret, wrote; + + mp = dbmp->mp; + if (nwrotep != NULL) + *nwrotep = 0; + + if (pct < 1 || pct > 100) + return (EINVAL); + + LOCKREGION(dbmp); + + /* + * If there are sufficient clean buffers, or no buffers or no dirty + * buffers, we're done. + * + * XXX + * Using st_page_clean and st_page_dirty is our only choice at the + * moment, but it's not as correct as we might like in the presence + * of pools with more than one buffer size, as a free 512-byte buffer + * isn't the same as a free 8K buffer. + */ +loop: total = mp->stat.st_page_clean + mp->stat.st_page_dirty; + if (total == 0 || mp->stat.st_page_dirty == 0 || + (mp->stat.st_page_clean * 100) / total >= (u_long)pct) { + UNLOCKREGION(dbmp); + return (0); + } + + /* Loop until we write a buffer. */ + for (bhp = SH_TAILQ_FIRST(&mp->bhq, __bh); + bhp != NULL; bhp = SH_TAILQ_NEXT(bhp, q, __bh)) { + if (bhp->ref != 0 || + !F_ISSET(bhp, BH_DIRTY) || F_ISSET(bhp, BH_LOCKED)) + continue; + + mfp = R_ADDR(dbmp, bhp->mf_offset); + if ((ret = + __memp_bhwrite(dbmp, mfp, bhp, ¬used, &wrote)) != 0) + goto err; + + /* + * Any process syncing the shared memory buffer pool + * had better be able to write to any underlying file. + * Be understanding, but firm, on this point. + */ + if (!wrote) { + __db_err(dbmp->dbenv, "%s: unable to flush page: %lu", + R_ADDR(dbmp, mfp->path_off), (u_long)bhp->pgno); + ret = EPERM; + goto err; + } + + ++mp->stat.st_page_trickle; + if (nwrotep != NULL) + ++*nwrotep; + goto loop; + } + + /* No more buffers to write. */ + return (0); + err: UNLOCKREGION(dbmp); + return (ret); +} + +static int +__bhcmp(p1, p2) + const void *p1, *p2; +{ + BH *bhp1, *bhp2; + + bhp1 = *(BH **)p1; + bhp2 = *(BH **)p2; + + /* Sort by file (shared memory pool offset). */ + if (bhp1->mf_offset < bhp2->mf_offset) + return (-1); + if (bhp1->mf_offset > bhp2->mf_offset) + return (1); - return (ret == 0 ? (pincnt ? DB_INCOMPLETE : 0) : ret); + /* Sort by page in file. */ + return (bhp1->pgno < bhp2->pgno ? -1 : 1); } |