From 80b231a0874aa5cd68c3d9f0dc7e13b6736a5dd3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Wed, 19 May 2010 15:21:15 +0200 Subject: sys.h: Correct the get_int64() macro The get_int64() macro has never been used (it was probably added for completeness at the same time that put_int64() was added), but it was not actually used and therefore it does not actually work. --- erts/emulator/beam/sys.h | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/erts/emulator/beam/sys.h b/erts/emulator/beam/sys.h index a1955235b7..0f20d36167 100644 --- a/erts/emulator/beam/sys.h +++ b/erts/emulator/beam/sys.h @@ -1173,14 +1173,14 @@ EXTERN_FUNCTION(void*, sys_calloc2, (Uint, Uint)); /* Standard set of integer macros .. */ -#define get_int64(s) ((((unsigned char*) (s))[0] << 56) | \ - (((unsigned char*) (s))[1] << 48) | \ - (((unsigned char*) (s))[2] << 40) | \ - (((unsigned char*) (s))[3] << 32) | \ - (((unsigned char*) (s))[4] << 24) | \ - (((unsigned char*) (s))[5] << 16) | \ - (((unsigned char*) (s))[6] << 8) | \ - (((unsigned char*) (s))[7])) +#define get_int64(s) (((Uint64)(((unsigned char*) (s))[0]) << 56) | \ + (((Uint64)((unsigned char*) (s))[1]) << 48) | \ + (((Uint64)((unsigned char*) (s))[2]) << 40) | \ + (((Uint64)((unsigned char*) (s))[3]) << 32) | \ + (((Uint64)((unsigned char*) (s))[4]) << 24) | \ + (((Uint64)((unsigned char*) (s))[5]) << 16) | \ + (((Uint64)((unsigned char*) (s))[6]) << 8) | \ + (((Uint64)((unsigned char*) (s))[7]))) #define put_int64(i, s) do {((char*)(s))[0] = (char)((Sint64)(i) >> 56) & 0xff;\ ((char*)(s))[1] = (char)((Sint64)(i) >> 48) & 0xff;\ -- cgit v1.2.3 From 3f53a96a8bd0cd4a18f819b6857e6a764706ede5 Mon Sep 17 00:00:00 2001 From: Filipe David Manana Date: Thu, 22 Apr 2010 23:40:26 +0100 Subject: Add file:datasync/1 for syncing file contents only file:datasync/1 invokes the POSIX system call "int fdatasync(int fd)". This system call is similar to "fsync" but, unlike fsync, it does not update the metadata associated with the file (like the access time for example). It's used by many DBMSs (MySQL and SQLite of example) to increase disk IO performance, as it avoids disk seeks and disk write operations compared to fsync. More details on it at: http://linux.die.net/man/2/fdatasync An example, from the MySQL source: http://bazaar.launchpad.net/~mysql/mysql-server/mysql-5.1-telco-6.1/annotate/head%3A/mysys/my_sync.c#L61 This new function just calls fsync on systems not implementing fdatasync. --- erts/configure.in | 6 ++++++ erts/emulator/drivers/common/efile_drv.c | 23 +++++++++++++++++++++++ erts/emulator/drivers/common/erl_efile.h | 1 + erts/emulator/drivers/common/ram_file_drv.c | 8 ++++++++ erts/emulator/drivers/unix/unix_efile.c | 11 +++++++++++ erts/emulator/drivers/win32/win_efile.c | 9 +++++++++ erts/preloaded/src/prim_file.erl | 6 +++++- lib/kernel/doc/src/file.xml | 27 +++++++++++++++++++++++++++ lib/kernel/src/file.erl | 12 +++++++++++- lib/kernel/src/file_io_server.erl | 8 ++++++++ lib/kernel/src/ram_file.erl | 5 ++++- lib/kernel/test/file_SUITE.erl | 28 ++++++++++++++++++++++++++-- lib/kernel/test/prim_file_SUITE.erl | 22 ++++++++++++++++++++-- 13 files changed, 159 insertions(+), 7 deletions(-) diff --git a/erts/configure.in b/erts/configure.in index a14b10adbf..f11aba1b15 100644 --- a/erts/configure.in +++ b/erts/configure.in @@ -1757,6 +1757,12 @@ fi dnl Need by run_erl. AC_CHECK_FUNCS([openpty]) +dnl fdatasync syscall (Unix only) +AC_CHECK_FUNCS([fdatasync]) + +dnl Find which C libraries are required to use fdatasync +AC_SEARCH_LIBS(fdatasync, [rt]) + dnl ---------------------------------------------------------------------- dnl Checks for features/quirks in the system that affects Erlang. dnl ---------------------------------------------------------------------- diff --git a/erts/emulator/drivers/common/efile_drv.c b/erts/emulator/drivers/common/efile_drv.c index d2b916000e..b64d27de68 100644 --- a/erts/emulator/drivers/common/efile_drv.c +++ b/erts/emulator/drivers/common/efile_drv.c @@ -53,6 +53,7 @@ #define FILE_IPREAD 27 #define FILE_ALTNAME 28 #define FILE_READ_LINE 29 +#define FILE_FDATASYNC 30 /* Return codes */ @@ -883,6 +884,15 @@ static void invoke_chdir(void *data) invoke_name(data, efile_chdir); } +static void invoke_fdatasync(void *data) +{ + struct t_data *d = (struct t_data *) data; + int fd = (int) d->fd; + + d->again = 0; + d->result_ok = efile_fdatasync(&d->errInfo, fd); +} + static void invoke_fsync(void *data) { struct t_data *d = (struct t_data *) data; @@ -1919,6 +1929,7 @@ file_async_ready(ErlDrvData e, ErlDrvThreadData data) case FILE_RMDIR: case FILE_CHDIR: case FILE_DELETE: + case FILE_FDATASYNC: case FILE_FSYNC: case FILE_TRUNCATE: case FILE_LINK: @@ -2209,6 +2220,18 @@ file_output(ErlDrvData e, char* buf, int count) goto done; } + case FILE_FDATASYNC: + { + d = EF_SAFE_ALLOC(sizeof(struct t_data)); + + d->fd = fd; + d->command = command; + d->invoke = invoke_fdatasync; + d->free = free_data; + d->level = 2; + goto done; + } + case FILE_FSYNC: { d = EF_SAFE_ALLOC(sizeof(struct t_data)); diff --git a/erts/emulator/drivers/common/erl_efile.h b/erts/emulator/drivers/common/erl_efile.h index 9aa941e550..6821a0e2ee 100644 --- a/erts/emulator/drivers/common/erl_efile.h +++ b/erts/emulator/drivers/common/erl_efile.h @@ -126,6 +126,7 @@ int efile_readdir(Efile_error* errInfo, char* name, int efile_openfile(Efile_error* errInfo, char* name, int flags, int* pfd, Sint64* pSize); void efile_closefile(int fd); +int efile_fdatasync(Efile_error* errInfo, int fd); int efile_fsync(Efile_error* errInfo, int fd); int efile_fileinfo(Efile_error* errInfo, Efile_info* pInfo, char *name, int info_for_link); diff --git a/erts/emulator/drivers/common/ram_file_drv.c b/erts/emulator/drivers/common/ram_file_drv.c index 4a39a156e6..d4e547ade6 100644 --- a/erts/emulator/drivers/common/ram_file_drv.c +++ b/erts/emulator/drivers/common/ram_file_drv.c @@ -35,6 +35,7 @@ #define RAM_FILE_TRUNCATE 14 #define RAM_FILE_PREAD 17 #define RAM_FILE_PWRITE 18 +#define RAM_FILE_FDATASYNC 19 /* other operations */ #define RAM_FILE_GET 30 @@ -558,6 +559,13 @@ static void rfile_command(ErlDrvData e, char* buf, int count) numeric_reply(f, 0); /* 0 is not used */ break; + case RAM_FILE_FDATASYNC: + if (f->flags == 0) + error_reply(f, EBADF); + else + reply(f, 1, 0); + break; + case RAM_FILE_FSYNC: if (f->flags == 0) error_reply(f, EBADF); diff --git a/erts/emulator/drivers/unix/unix_efile.c b/erts/emulator/drivers/unix/unix_efile.c index 1d094ee613..0cece76221 100644 --- a/erts/emulator/drivers/unix/unix_efile.c +++ b/erts/emulator/drivers/unix/unix_efile.c @@ -773,6 +773,17 @@ efile_closefile(int fd) close(fd); } +int +efile_fdatasync(Efile_error *errInfo, /* Where to return error codes. */ + int fd) /* File descriptor for file to sync data. */ +{ +#ifdef HAVE_FDATASYNC + return check_error(fdatasync(fd), errInfo); +#else + return efile_fsync(errInfo, fd); +#endif +} + int efile_fsync(Efile_error *errInfo, /* Where to return error codes. */ int fd) /* File descriptor for file to sync. */ diff --git a/erts/emulator/drivers/win32/win_efile.c b/erts/emulator/drivers/win32/win_efile.c index 89aaad31da..cdf3bb424c 100644 --- a/erts/emulator/drivers/win32/win_efile.c +++ b/erts/emulator/drivers/win32/win_efile.c @@ -763,6 +763,15 @@ int fd; /* File descriptor for file to close. */ CloseHandle((HANDLE) fd); } +int +efile_fdatasync(errInfo, fd) +Efile_error* errInfo; /* Where to return error codes. */ +int fd; /* File descriptor for file to sync. */ +{ + /* Not available in Windows, just call regular fsync */ + return efile_fsync(errInfo, fd); +} + int efile_fsync(errInfo, fd) Efile_error* errInfo; /* Where to return error codes. */ diff --git a/erts/preloaded/src/prim_file.erl b/erts/preloaded/src/prim_file.erl index 43e6f6cd88..53c741e66e 100644 --- a/erts/preloaded/src/prim_file.erl +++ b/erts/preloaded/src/prim_file.erl @@ -25,7 +25,7 @@ %%% Interface towards a single file's contents. Uses ?FD_DRV. %% Generic file contents operations --export([open/2, close/1, sync/1, position/2, truncate/1, +-export([open/2, close/1, datasync/1, sync/1, position/2, truncate/1, write/2, pwrite/2, pwrite/3, read/2, read_line/1, pread/2, pread/3, copy/3]). %% Specialized file operations @@ -96,6 +96,7 @@ -define(FILE_IPREAD, 27). -define(FILE_ALTNAME, 28). -define(FILE_READ_LINE, 29). +-define(FILE_FDATASYNC, 30). %% Driver responses -define(FILE_RESP_OK, 0). @@ -292,6 +293,9 @@ pwrite(#file_descriptor{module = ?MODULE}, _, _) -> {error, badarg}. +%% Returns {error, Reason} | ok. +datasync(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> + drv_command(Port, [?FILE_FDATASYNC]). %% Returns {error, Reason} | ok. sync(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> diff --git a/lib/kernel/doc/src/file.xml b/lib/kernel/doc/src/file.xml index 50f9722a1c..c94df62d1f 100644 --- a/lib/kernel/doc/src/file.xml +++ b/lib/kernel/doc/src/file.xml @@ -1640,6 +1640,33 @@ f.txt: {person, "kalle", 25}. + + datasync(IoDevice) -> ok | {error, Reason} + Synchronizes the in-memory data of a file, ignoring most of its metadata, with that on the physical medium + + IoDevice = io_device() + Reason = ext_posix() | terminated + + +

Makes sure that any buffers kept by the operating system + (not by the Erlang runtime system) are written to disk. In + many ways it's resembles fsync but it not requires to update + some of file's metadata such as the access time. On + some platforms, this function might have no effect.

+

Applications that access databases or log files often write + a tiny data fragment (e.g., one line in a log file) and then + call fsync() immediately in order to ensure that the written + data is physically stored on the harddisk. Unfortunately, fsync() + will always initiate two write operations: one for the newly + written data and another one in order to update the modification + time stored in the inode. If the modification time is not a part + of the transaction concept fdatasync() can be used to avoid + unnecessary inode disk write operations.

+

Available only in some POSIX systems. This call results in a + call to fsync(), or has no effect, in systems not implementing + the fdatasync syscall.

+ + truncate(IoDevice) -> ok | {error, Reason} Truncate a file diff --git a/lib/kernel/src/file.erl b/lib/kernel/src/file.erl index 46ffa9d708..5da359fdf1 100644 --- a/lib/kernel/src/file.erl +++ b/lib/kernel/src/file.erl @@ -40,7 +40,7 @@ read/2, write/2, pread/2, pread/3, pwrite/2, pwrite/3, read_line/1, - position/2, truncate/1, sync/1, + position/2, truncate/1, datasync/1, sync/1, copy/2, copy/3]). %% High level operations -export([consult/1, path_consult/2]). @@ -472,6 +472,16 @@ pwrite(#file_descriptor{module = Module} = Handle, Offs, Bytes) -> pwrite(_, _, _) -> {error, badarg}. +-spec datasync(File :: io_device()) -> 'ok' | {'error', posix()}. + +datasync(File) when is_pid(File) -> + R = file_request(File, datasync), + wait_file_reply(File, R); +datasync(#file_descriptor{module = Module} = Handle) -> + Module:datasync(Handle); +datasync(_) -> + {error, badarg}. + -spec sync(File :: io_device()) -> 'ok' | {'error', posix()}. sync(File) when is_pid(File) -> diff --git a/lib/kernel/src/file_io_server.erl b/lib/kernel/src/file_io_server.erl index 3ac35a209d..d0b30192b3 100644 --- a/lib/kernel/src/file_io_server.erl +++ b/lib/kernel/src/file_io_server.erl @@ -219,6 +219,14 @@ file_request({pwrite,At,Data}, Reply -> std_reply(Reply, State) end; +file_request(datasync, + #state{handle=Handle}=State) -> + case ?PRIM_FILE:datasync(Handle) of + {error,_}=Reply -> + {stop,normal,Reply,State}; + Reply -> + {reply,Reply,State} + end; file_request(sync, #state{handle=Handle}=State) -> case ?PRIM_FILE:sync(Handle) of diff --git a/lib/kernel/src/ram_file.erl b/lib/kernel/src/ram_file.erl index d996650948..0230cb4e0a 100644 --- a/lib/kernel/src/ram_file.erl +++ b/lib/kernel/src/ram_file.erl @@ -24,7 +24,7 @@ -export([open/2, close/1]). -export([write/2, read/2, copy/3, pread/2, pread/3, pwrite/2, pwrite/3, - position/2, truncate/1, sync/1]). + position/2, truncate/1, datasync/1, sync/1]). %% Specialized file operations -export([get_size/1, get_file/1, set_file/2, get_file_close/1]). @@ -60,6 +60,7 @@ -define(RAM_FILE_TRUNCATE, 14). -define(RAM_FILE_PREAD, 17). -define(RAM_FILE_PWRITE, 18). +-define(RAM_FILE_FDATASYNC, 19). %% Other operations -define(RAM_FILE_GET, 30). @@ -167,6 +168,8 @@ copy(#file_descriptor{module = ?MODULE} = Source, %% XXX Should be moved down to the driver for optimization. file:copy_opened(Source, Dest, Length). +datasync(#file_descriptor{module = ?MODULE, data = Port}) -> + call_port(Port, <>). sync(#file_descriptor{module = ?MODULE, data = Port}) -> call_port(Port, <>). diff --git a/lib/kernel/test/file_SUITE.erl b/lib/kernel/test/file_SUITE.erl index 1d170790a3..2e6c3aba16 100644 --- a/lib/kernel/test/file_SUITE.erl +++ b/lib/kernel/test/file_SUITE.erl @@ -52,7 +52,7 @@ old_modes/1, new_modes/1, path_open/1, open_errors/1]). -export([file_info/1, file_info_basic_file/1, file_info_basic_directory/1, file_info_bad/1, file_info_times/1, file_write_file_info/1]). --export([rename/1, access/1, truncate/1, sync/1, +-export([rename/1, access/1, truncate/1, datasync/1, sync/1, read_write/1, pread_write/1, append/1]). -export([errors/1, e_delete/1, e_rename/1, e_make_dir/1, e_del_dir/1]). -export([otp_5814/1]). @@ -377,7 +377,7 @@ win_cur_dir_1(_Config) -> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -files(suite) -> [open,pos,file_info,consult,eval,script,truncate,sync]. +files(suite) -> [open,pos,file_info,consult,eval,script,truncate,sync,datasync]. open(suite) -> [open1,old_modes,new_modes,path_open,close,access,read_write, pread_write,append,open_errors]. @@ -1355,6 +1355,30 @@ truncate(Config) when is_list(Config) -> ok. +datasync(suite) -> []; +datasync(doc) -> "Tests that ?FILE_MODULE:datasync/1 at least doesn't crash."; +datasync(Config) when is_list(Config) -> + ?line Dog = test_server:timetrap(test_server:seconds(5)), + ?line PrivDir = ?config(priv_dir, Config), + ?line Sync = filename:join(PrivDir, + atom_to_list(?MODULE) + ++"_sync.fil"), + + %% Raw open. + ?line {ok, Fd} = ?FILE_MODULE:open(Sync, [write, raw]), + ?line ok = ?FILE_MODULE:datasync(Fd), + ?line ok = ?FILE_MODULE:close(Fd), + + %% Ordinary open. + ?line {ok, Fd2} = ?FILE_MODULE:open(Sync, [write]), + ?line ok = ?FILE_MODULE:datasync(Fd2), + ?line ok = ?FILE_MODULE:close(Fd2), + + ?line [] = flush(), + ?line test_server:timetrap_cancel(Dog), + ok. + + sync(suite) -> []; sync(doc) -> "Tests that ?FILE_MODULE:sync/1 at least doesn't crash."; sync(Config) when is_list(Config) -> diff --git a/lib/kernel/test/prim_file_SUITE.erl b/lib/kernel/test/prim_file_SUITE.erl index 6badbb5090..842945e83c 100644 --- a/lib/kernel/test/prim_file_SUITE.erl +++ b/lib/kernel/test/prim_file_SUITE.erl @@ -34,7 +34,7 @@ file_info_times_a/1, file_info_times_b/1, file_write_file_info_a/1, file_write_file_info_b/1]). -export([rename_a/1, rename_b/1, - access/1, truncate/1, sync/1, + access/1, truncate/1, datasync/1, sync/1, read_write/1, pread_write/1, append/1]). -export([errors/1, e_delete/1, e_rename/1, e_make_dir/1, e_del_dir/1]). @@ -380,7 +380,7 @@ win_cur_dir_1(_Config, Handle) -> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -files(suite) -> [open,pos,file_info,truncate,sync]. +files(suite) -> [open,pos,file_info,truncate,sync,datasync]. open(suite) -> [open1,modes,close,access,read_write, pread_write,append]. @@ -1064,6 +1064,24 @@ truncate(Config) when is_list(Config) -> ok. +datasync(suite) -> []; +datasync(doc) -> "Tests that ?PRIM_FILE:datasync/1 at least doesn't crash."; +datasync(Config) when is_list(Config) -> + ?line Dog = test_server:timetrap(test_server:seconds(5)), + ?line PrivDir = ?config(priv_dir, Config), + ?line Sync = filename:join(PrivDir, + atom_to_list(?MODULE) + ++"_sync.fil"), + + %% Raw open. + ?line {ok, Fd} = ?PRIM_FILE:open(Sync, [write]), + ?line ok = ?PRIM_FILE:datasync(Fd), + ?line ok = ?PRIM_FILE:close(Fd), + + ?line test_server:timetrap_cancel(Dog), + ok. + + sync(suite) -> []; sync(doc) -> "Tests that ?PRIM_FILE:sync/1 at least doesn't crash."; sync(Config) when is_list(Config) -> -- cgit v1.2.3 From 21a67b797e40df930b83bd407ffc165b3f4b91b2 Mon Sep 17 00:00:00 2001 From: Filipe David Manana Date: Mon, 26 Apr 2010 13:04:40 +0200 Subject: Add file:advise/4 - a wrapper to the POSIX syscall posix_fadvise Useful for informing the Operating System about the access pattern for a file's data, so that it can adapt the caching strategy to maximize disk IO performance. --- erts/configure.in | 1 + erts/emulator/drivers/common/efile_drv.c | 34 +++++++++++++ erts/emulator/drivers/common/erl_efile.h | 2 + erts/emulator/drivers/common/ram_file_drv.c | 9 ++++ erts/emulator/drivers/unix/unix_efile.c | 11 +++++ erts/emulator/drivers/win32/win_efile.c | 9 ++++ erts/preloaded/src/prim_file.erl | 38 +++++++++++++- lib/kernel/doc/src/file.xml | 19 +++++++ lib/kernel/src/file.erl | 16 +++++- lib/kernel/src/file_io_server.erl | 8 +++ lib/kernel/src/ram_file.erl | 33 ++++++++++++- lib/kernel/test/file_SUITE.erl | 77 ++++++++++++++++++++++++++++- lib/kernel/test/prim_file_SUITE.erl | 75 +++++++++++++++++++++++++++- 13 files changed, 327 insertions(+), 5 deletions(-) diff --git a/erts/configure.in b/erts/configure.in index f11aba1b15..63bf548c89 100644 --- a/erts/configure.in +++ b/erts/configure.in @@ -1054,6 +1054,7 @@ fi AC_SUBST(ERTS_BUILD_SMP_EMU) +AC_CHECK_FUNCS([posix_fadvise]) # diff --git a/erts/emulator/drivers/common/efile_drv.c b/erts/emulator/drivers/common/efile_drv.c index b64d27de68..60ae4cb108 100644 --- a/erts/emulator/drivers/common/efile_drv.c +++ b/erts/emulator/drivers/common/efile_drv.c @@ -54,6 +54,7 @@ #define FILE_ALTNAME 28 #define FILE_READ_LINE 29 #define FILE_FDATASYNC 30 +#define FILE_FADVISE 31 /* Return codes */ @@ -358,6 +359,11 @@ struct t_data struct t_readdir_buf *first_buf; struct t_readdir_buf *last_buf; } read_dir; + struct { + Sint64 offset; + Sint64 length; + int advise; + } fadvise; } c; char b[1]; }; @@ -1647,6 +1653,18 @@ static void invoke_open(void *data) d->result_ok = status; } +static void invoke_fadvise(void *data) +{ + struct t_data *d = (struct t_data *) data; + int fd = (int) d->fd; + off_t offset = (off_t) d->c.fadvise.offset; + off_t length = (off_t) d->c.fadvise.length; + int advise = (int) d->c.fadvise.advise; + + d->again = 0; + d->result_ok = efile_fadvise(&d->errInfo, fd, offset, length, advise); +} + static void free_readdir(void *data) { struct t_data *d = (struct t_data *) data; @@ -1936,6 +1954,7 @@ file_async_ready(ErlDrvData e, ErlDrvThreadData data) case FILE_SYMLINK: case FILE_RENAME: case FILE_WRITE_INFO: + case FILE_FADVISE: reply(desc, d->result_ok, &d->errInfo); free_data(data); break; @@ -2355,6 +2374,21 @@ file_output(ErlDrvData e, char* buf, int count) goto done; } + case FILE_FADVISE: + { + d = EF_SAFE_ALLOC(sizeof(struct t_data)); + + d->fd = fd; + d->command = command; + d->invoke = invoke_fadvise; + d->free = free_data; + d->level = 2; + d->c.fadvise.offset = get_int64((uchar*) buf); + d->c.fadvise.length = get_int64(((uchar*) buf) + sizeof(Sint64)); + d->c.fadvise.advise = get_int32(((uchar*) buf) + 2 * sizeof(Sint64)); + goto done; + } + } /* diff --git a/erts/emulator/drivers/common/erl_efile.h b/erts/emulator/drivers/common/erl_efile.h index 6821a0e2ee..61684af6c9 100644 --- a/erts/emulator/drivers/common/erl_efile.h +++ b/erts/emulator/drivers/common/erl_efile.h @@ -151,3 +151,5 @@ int efile_altname(Efile_error* errInfo, char *name, int efile_link(Efile_error* errInfo, char* old, char* new); int efile_symlink(Efile_error* errInfo, char* old, char* new); int efile_may_openfile(Efile_error* errInfo, char *name); +int efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset, Sint64 length, + int advise); diff --git a/erts/emulator/drivers/common/ram_file_drv.c b/erts/emulator/drivers/common/ram_file_drv.c index d4e547ade6..abedcc933a 100644 --- a/erts/emulator/drivers/common/ram_file_drv.c +++ b/erts/emulator/drivers/common/ram_file_drv.c @@ -46,6 +46,8 @@ #define RAM_FILE_UUENCODE 35 /* uuencode file */ #define RAM_FILE_UUDECODE 36 /* uudecode file */ #define RAM_FILE_SIZE 37 /* get file size */ +#define RAM_FILE_ADVISE 38 /* predeclare the access + * pattern for file data */ /* possible new operations include: DES_ENCRYPT DES_DECRYPT @@ -693,6 +695,13 @@ static void rfile_command(ErlDrvData e, char* buf, int count) case RAM_FILE_UUDECODE: /* uudecode file */ ram_file_uudecode(f); break; + + case RAM_FILE_ADVISE: + if (f->flags == 0) + error_reply(f, EBADF); + else + reply(f, 1, 0); + break; } /* * Ignore anything else -- let the caller hang. diff --git a/erts/emulator/drivers/unix/unix_efile.c b/erts/emulator/drivers/unix/unix_efile.c index 0cece76221..ea016526ef 100644 --- a/erts/emulator/drivers/unix/unix_efile.c +++ b/erts/emulator/drivers/unix/unix_efile.c @@ -1448,3 +1448,14 @@ efile_symlink(Efile_error* errInfo, char* old, char* new) return check_error(symlink(old, new), errInfo); #endif } + +int +efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset, + Sint64 length, int advise) +{ +#ifdef HAVE_POSIX_FADVISE + return check_error(posix_fadvise(fd, offset, length, advise), errInfo); +#else + return check_error(0, errInfo); +#endif +} diff --git a/erts/emulator/drivers/win32/win_efile.c b/erts/emulator/drivers/win32/win_efile.c index cdf3bb424c..06850b4945 100644 --- a/erts/emulator/drivers/win32/win_efile.c +++ b/erts/emulator/drivers/win32/win_efile.c @@ -1433,3 +1433,12 @@ efile_symlink(Efile_error* errInfo, char* old, char* new) errno = ENOTSUP; return check_error(-1, errInfo); } + +int +efile_fadvise(Efile_error* errInfo, int fd, Sint64 offset, + Sint64 length, int advise) +{ + /* posix_fadvise is not available on Windows, do nothing */ + errno = ERROR_SUCCESS; + return check_error(0, errInfo); +} diff --git a/erts/preloaded/src/prim_file.erl b/erts/preloaded/src/prim_file.erl index 53c741e66e..e9df5752ab 100644 --- a/erts/preloaded/src/prim_file.erl +++ b/erts/preloaded/src/prim_file.erl @@ -25,7 +25,7 @@ %%% Interface towards a single file's contents. Uses ?FD_DRV. %% Generic file contents operations --export([open/2, close/1, datasync/1, sync/1, position/2, truncate/1, +-export([open/2, close/1, datasync/1, sync/1, advise/4, position/2, truncate/1, write/2, pwrite/2, pwrite/3, read/2, read_line/1, pread/2, pread/3, copy/3]). %% Specialized file operations @@ -97,6 +97,7 @@ -define(FILE_ALTNAME, 28). -define(FILE_READ_LINE, 29). -define(FILE_FDATASYNC, 30). +-define(FILE_ADVISE, 31). %% Driver responses -define(FILE_RESP_OK, 0). @@ -131,6 +132,13 @@ %% IPREAD variants -define(IPREAD_S32BU_P32BU, 0). +%% POSIX file advises +-define(POSIX_FADV_NORMAL, 0). +-define(POSIX_FADV_RANDOM, 1). +-define(POSIX_FADV_SEQUENTIAL, 2). +-define(POSIX_FADV_WILLNEED, 3). +-define(POSIX_FADV_DONTNEED, 4). +-define(POSIX_FADV_NOREUSE, 5). %%%----------------------------------------------------------------- @@ -221,7 +229,35 @@ close(#file_descriptor{module = ?MODULE, data = {Port, _}}) -> close(Port) when is_port(Port) -> drv_close(Port). +-define(ADVISE(Offs, Len, Adv), + <>). +%% Returns {error, Reason} | ok. +advise(#file_descriptor{module = ?MODULE, data = {Port, _}}, + Offset, Length, Advise) -> + case Advise of + normal -> + Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NORMAL), + drv_command(Port, Cmd); + random -> + Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_RANDOM), + drv_command(Port, Cmd); + sequential -> + Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_SEQUENTIAL), + drv_command(Port, Cmd); + will_need -> + Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_WILLNEED), + drv_command(Port, Cmd); + dont_need -> + Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_DONTNEED), + drv_command(Port, Cmd); + no_reuse -> + Cmd = ?ADVISE(Offset, Length, ?POSIX_FADV_NOREUSE), + drv_command(Port, Cmd); + _ -> + {error, einval} + end. %% Returns {error, Reason} | ok. write(#file_descriptor{module = ?MODULE, data = {Port, _}}, Bytes) -> diff --git a/lib/kernel/doc/src/file.xml b/lib/kernel/doc/src/file.xml index c94df62d1f..382262d1ee 100644 --- a/lib/kernel/doc/src/file.xml +++ b/lib/kernel/doc/src/file.xml @@ -61,6 +61,25 @@ time() = {{Year, Month, Day}, {Hour, Minute, Second}} Must denote a valid date and time + + advise(IoDevice, Offset, Length, Advise) -> ok | {error, Reason} + Predeclare an access pattern for file data + + IoDevice = io_device() + Offset = int() + Length = int() + Advise = posix_file_advise() + posix_file_advise() = normal | sequential | random | no_reuse + | will_need | dont_need + Reason = ext_posix() + + +

advise/4 can be used to announce an intention to access file + data in a specific pattern in the future, thus allowing the + operating system to perform appropriate optimizations.

+

On some platforms, this function might have no effect.

+ + change_group(Filename, Gid) -> ok | {error, Reason} Change group of a file diff --git a/lib/kernel/src/file.erl b/lib/kernel/src/file.erl index 5da359fdf1..a694ed0708 100644 --- a/lib/kernel/src/file.erl +++ b/lib/kernel/src/file.erl @@ -36,7 +36,7 @@ %% Specialized -export([ipread_s32bu_p32bu/3]). %% Generic file contents. --export([open/2, close/1, +-export([open/2, close/1, advise/4, read/2, write/2, pread/2, pread/3, pwrite/2, pwrite/3, read_line/1, @@ -89,6 +89,8 @@ -type date() :: {pos_integer(), pos_integer(), pos_integer()}. -type time() :: {non_neg_integer(), non_neg_integer(), non_neg_integer()}. -type date_time() :: {date(), time()}. +-type posix_file_advise() :: 'normal' | 'sequential' | 'random' | 'no_reuse' | + 'will_need' | 'dont_need'. %%%----------------------------------------------------------------- %%% General functions @@ -352,6 +354,18 @@ close(#file_descriptor{module = Module} = Handle) -> close(_) -> {error, badarg}. +-spec advise(File :: io_device(), Offset :: integer(), + Length :: integer(), Advise :: posix_file_advise()) -> + 'ok' | {'error', posix()}. + +advise(File, Offset, Length, Advise) when is_pid(File) -> + R = file_request(File, {advise, Offset, Length, Advise}), + wait_file_reply(File, R); +advise(#file_descriptor{module = Module} = Handle, Offset, Length, Advise) -> + Module:advise(Handle, Offset, Length, Advise); +advise(_, _, _, _) -> + {error, badarg}. + -spec read(File :: io_device(), Size :: non_neg_integer()) -> 'eof' | {'ok', [char()] | binary()} | {'error', posix()}. diff --git a/lib/kernel/src/file_io_server.erl b/lib/kernel/src/file_io_server.erl index d0b30192b3..39dc32bb79 100644 --- a/lib/kernel/src/file_io_server.erl +++ b/lib/kernel/src/file_io_server.erl @@ -198,6 +198,14 @@ io_reply(From, ReplyAs, Reply) -> %%%----------------------------------------------------------------- %%% file requests +file_request({advise,Offset,Length,Advise}, + #state{handle=Handle}=State) -> + case ?PRIM_FILE:advise(Handle, Offset, Length, Advise) of + {error,_}=Reply -> + {stop,normal,Reply,State}; + Reply -> + {reply,Reply,State} + end; file_request({pread,At,Sz}, #state{handle=Handle,buf=Buf,read_mode=ReadMode}=State) -> case position(Handle, At, Buf) of diff --git a/lib/kernel/src/ram_file.erl b/lib/kernel/src/ram_file.erl index 0230cb4e0a..2bfb2cd021 100644 --- a/lib/kernel/src/ram_file.erl +++ b/lib/kernel/src/ram_file.erl @@ -28,7 +28,7 @@ %% Specialized file operations -export([get_size/1, get_file/1, set_file/2, get_file_close/1]). --export([compress/1, uncompress/1, uuencode/1, uudecode/1]). +-export([compress/1, uncompress/1, uuencode/1, uudecode/1, advise/4]). -export([open_mode/1]). %% used by ftp-file @@ -71,6 +71,7 @@ -define(RAM_FILE_UUENCODE, 35). -define(RAM_FILE_UUDECODE, 36). -define(RAM_FILE_SIZE, 37). +-define(RAM_FILE_ADVISE, 38). %% Open modes for RAM_FILE_OPEN -define(RAM_FILE_MODE_READ, 1). @@ -91,6 +92,14 @@ -define(RAM_FILE_RESP_NUMBER, 3). -define(RAM_FILE_RESP_INFO, 4). +%% POSIX file advises +-define(POSIX_FADV_NORMAL, 0). +-define(POSIX_FADV_RANDOM, 1). +-define(POSIX_FADV_SEQUENTIAL, 2). +-define(POSIX_FADV_WILLNEED, 3). +-define(POSIX_FADV_DONTNEED, 4). +-define(POSIX_FADV_NOREUSE, 5). + %% -------------------------------------------------------------------------- %% Generic file contents operations. %% @@ -352,6 +361,28 @@ uudecode(#file_descriptor{module = ?MODULE, data = Port}) -> uudecode(#file_descriptor{}) -> {error, enotsup}. +advise(#file_descriptor{module = ?MODULE, data = Port}, Offset, + Length, Advise) -> + Cmd0 = <>, + case Advise of + normal -> + call_port(Port, <>); + random -> + call_port(Port, <>); + sequential -> + call_port(Port, <>); + will_need -> + call_port(Port, <>); + dont_need -> + call_port(Port, <>); + no_reuse -> + call_port(Port, <>); + _ -> + {error, einval} + end; +advise(#file_descriptor{}, _Offset, _Length, _Advise) -> + {error, enotsup}. + %%%----------------------------------------------------------------- diff --git a/lib/kernel/test/file_SUITE.erl b/lib/kernel/test/file_SUITE.erl index 2e6c3aba16..1d652679b0 100644 --- a/lib/kernel/test/file_SUITE.erl +++ b/lib/kernel/test/file_SUITE.erl @@ -82,6 +82,8 @@ -export([read_line_1/1, read_line_2/1, read_line_3/1,read_line_4/1]). +-export([advise/1]). + %% Debug exports -export([create_file_slow/2, create_file/2, create_bin/2]). -export([verify_file/2, verify_bin/3]). @@ -377,7 +379,9 @@ win_cur_dir_1(_Config) -> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -files(suite) -> [open,pos,file_info,consult,eval,script,truncate,sync,datasync]. +files(suite) -> + [open,pos,file_info,consult,eval,script,truncate, + sync,datasync,advise]. open(suite) -> [open1,old_modes,new_modes,path_open,close,access,read_write, pread_write,append,open_errors]. @@ -1402,6 +1406,77 @@ sync(Config) when is_list(Config) -> ?line test_server:timetrap_cancel(Dog), ok. +advise(suite) -> []; +advise(doc) -> "Tests that ?FILE_MODULE:advise/4 at least doesn't crash."; +advise(Config) when is_list(Config) -> + ?line Dog = test_server:timetrap(test_server:seconds(5)), + ?line PrivDir = ?config(priv_dir, Config), + ?line Advise = filename:join(PrivDir, + atom_to_list(?MODULE) + ++"_advise.fil"), + + Line1 = "Hello\n", + Line2 = "World!\n", + + ?line {ok, Fd} = ?FILE_MODULE:open(Advise, [write]), + ?line ok = ?FILE_MODULE:advise(Fd, 0, 0, normal), + ?line ok = io:format(Fd, "~s", [Line1]), + ?line ok = io:format(Fd, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd), + + ?line {ok, Fd2} = ?FILE_MODULE:open(Advise, [write]), + ?line ok = ?FILE_MODULE:advise(Fd2, 0, 0, random), + ?line ok = io:format(Fd2, "~s", [Line1]), + ?line ok = io:format(Fd2, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd2), + + ?line {ok, Fd3} = ?FILE_MODULE:open(Advise, [write]), + ?line ok = ?FILE_MODULE:advise(Fd3, 0, 0, sequential), + ?line ok = io:format(Fd3, "~s", [Line1]), + ?line ok = io:format(Fd3, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd3), + + ?line {ok, Fd4} = ?FILE_MODULE:open(Advise, [write]), + ?line ok = ?FILE_MODULE:advise(Fd4, 0, 0, will_need), + ?line ok = io:format(Fd4, "~s", [Line1]), + ?line ok = io:format(Fd4, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd4), + + ?line {ok, Fd5} = ?FILE_MODULE:open(Advise, [write]), + ?line ok = ?FILE_MODULE:advise(Fd5, 0, 0, dont_need), + ?line ok = io:format(Fd5, "~s", [Line1]), + ?line ok = io:format(Fd5, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd5), + + ?line {ok, Fd6} = ?FILE_MODULE:open(Advise, [write]), + ?line ok = ?FILE_MODULE:advise(Fd6, 0, 0, no_reuse), + ?line ok = io:format(Fd6, "~s", [Line1]), + ?line ok = io:format(Fd6, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd6), + + ?line {ok, Fd7} = ?FILE_MODULE:open(Advise, [write]), + ?line {error, einval} = ?FILE_MODULE:advise(Fd7, 0, 0, bad_advise), + ?line ok = ?FILE_MODULE:close(Fd7), + + %% test write without advise, then a read after an advise + ?line {ok, Fd8} = ?FILE_MODULE:open(Advise, [write]), + ?line ok = io:format(Fd8, "~s", [Line1]), + ?line ok = io:format(Fd8, "~s", [Line2]), + ?line ok = ?FILE_MODULE:close(Fd8), + ?line {ok, Fd9} = ?FILE_MODULE:open(Advise, [read]), + Offset = 0, + %% same as a 0 length in some implementations + Length = length(Line1) + length(Line2), + ?line ok = ?FILE_MODULE:advise(Fd9, Offset, Length, sequential), + ?line {ok, Line1} = ?FILE_MODULE:read_line(Fd9), + ?line {ok, Line2} = ?FILE_MODULE:read_line(Fd9), + ?line eof = ?FILE_MODULE:read_line(Fd9), + ?line ok = ?FILE_MODULE:close(Fd9), + + ?line [] = flush(), + ?line test_server:timetrap_cancel(Dog), + ok. + %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% diff --git a/lib/kernel/test/prim_file_SUITE.erl b/lib/kernel/test/prim_file_SUITE.erl index 842945e83c..21bdc06fdc 100644 --- a/lib/kernel/test/prim_file_SUITE.erl +++ b/lib/kernel/test/prim_file_SUITE.erl @@ -48,6 +48,8 @@ symlinks_a/1, symlinks_b/1, list_dir_limit/1]). +-export([advise/1]). + -include("test_server.hrl"). -include_lib("kernel/include/file.hrl"). @@ -380,7 +382,7 @@ win_cur_dir_1(_Config, Handle) -> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -files(suite) -> [open,pos,file_info,truncate,sync,datasync]. +files(suite) -> [open,pos,file_info,truncate,sync,datasync,advise]. open(suite) -> [open1,modes,close,access,read_write, pread_write,append]. @@ -1100,6 +1102,77 @@ sync(Config) when is_list(Config) -> ok. +advise(suite) -> []; +advise(doc) -> "Tests that ?PRIM_FILE:advise/4 at least doesn't crash."; +advise(Config) when is_list(Config) -> + ?line Dog = test_server:timetrap(test_server:seconds(5)), + ?line PrivDir = ?config(priv_dir, Config), + ?line Advise = filename:join(PrivDir, + atom_to_list(?MODULE) + ++"_advise.fil"), + + Line1 = "Hello\n", + Line2 = "World!\n", + + ?line {ok, Fd} = ?PRIM_FILE:open(Advise, [write]), + ?line ok = ?PRIM_FILE:advise(Fd, 0, 0, normal), + ?line ok = ?PRIM_FILE:write(Fd, Line1), + ?line ok = ?PRIM_FILE:write(Fd, Line2), + ?line ok = ?PRIM_FILE:close(Fd), + + ?line {ok, Fd2} = ?PRIM_FILE:open(Advise, [write]), + ?line ok = ?PRIM_FILE:advise(Fd2, 0, 0, random), + ?line ok = ?PRIM_FILE:write(Fd2, Line1), + ?line ok = ?PRIM_FILE:write(Fd2, Line2), + ?line ok = ?PRIM_FILE:close(Fd2), + + ?line {ok, Fd3} = ?PRIM_FILE:open(Advise, [write]), + ?line ok = ?PRIM_FILE:advise(Fd3, 0, 0, sequential), + ?line ok = ?PRIM_FILE:write(Fd3, Line1), + ?line ok = ?PRIM_FILE:write(Fd3, Line2), + ?line ok = ?PRIM_FILE:close(Fd3), + + ?line {ok, Fd4} = ?PRIM_FILE:open(Advise, [write]), + ?line ok = ?PRIM_FILE:advise(Fd4, 0, 0, will_need), + ?line ok = ?PRIM_FILE:write(Fd4, Line1), + ?line ok = ?PRIM_FILE:write(Fd4, Line2), + ?line ok = ?PRIM_FILE:close(Fd4), + + ?line {ok, Fd5} = ?PRIM_FILE:open(Advise, [write]), + ?line ok = ?PRIM_FILE:advise(Fd5, 0, 0, dont_need), + ?line ok = ?PRIM_FILE:write(Fd5, Line1), + ?line ok = ?PRIM_FILE:write(Fd5, Line2), + ?line ok = ?PRIM_FILE:close(Fd5), + + ?line {ok, Fd6} = ?PRIM_FILE:open(Advise, [write]), + ?line ok = ?PRIM_FILE:advise(Fd6, 0, 0, no_reuse), + ?line ok = ?PRIM_FILE:write(Fd6, Line1), + ?line ok = ?PRIM_FILE:write(Fd6, Line2), + ?line ok = ?PRIM_FILE:close(Fd6), + + ?line {ok, Fd7} = ?PRIM_FILE:open(Advise, [write]), + ?line {error, einval} = ?PRIM_FILE:advise(Fd7, 0, 0, bad_advise), + ?line ok = ?PRIM_FILE:close(Fd7), + + %% test write without advise, then a read after an advise + ?line {ok, Fd8} = ?PRIM_FILE:open(Advise, [write]), + ?line ok = ?PRIM_FILE:write(Fd8, Line1), + ?line ok = ?PRIM_FILE:write(Fd8, Line2), + ?line ok = ?PRIM_FILE:close(Fd8), + ?line {ok, Fd9} = ?PRIM_FILE:open(Advise, [read]), + Offset = 0, + %% same as a 0 length in some implementations + Length = length(Line1) + length(Line2), + ?line ok = ?PRIM_FILE:advise(Fd9, Offset, Length, sequential), + ?line {ok, Line1} = ?PRIM_FILE:read_line(Fd9), + ?line {ok, Line2} = ?PRIM_FILE:read_line(Fd9), + ?line eof = ?PRIM_FILE:read_line(Fd9), + ?line ok = ?PRIM_FILE:close(Fd9), + + ?line test_server:timetrap_cancel(Dog), + ok. + + %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% delete_a(suite) -> []; 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