hardlink: rename --buffer-size to --io-size

Addresses: https://github.com/karelzak/util-linux/pull/1467
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/misc-utils/hardlink.1.adoc b/misc-utils/hardlink.1.adoc
index cf7ce72bd52ccbbbff47d93a7a10afe73745d30c..bdd83d0978f1d7319ea81dc64a1ae5f316fc51f9 100644 (file)
--- a/misc-utils/hardlink.1.adoc
+++ b/misc-utils/hardlink.1.adoc
@@ -78,12 +78,13 @@ A regular expression to include files. If the option *--exclude* has been given,
 *-s*, *--minimum-size* _size_::
 The minimum size to consider. By default this is 1, so empty files will not be linked. The _size_ argument may be followed by the multiplicative suffixes KiB (=1024), MiB (=1024*1024), and so on for GiB, TiB, PiB, EiB, ZiB and YiB (the "iB" is optional, e.g., "K" has the same meaning as "KiB").
 
-*-S*, *--buffer-size* _size_::
-The size of read buffer used when comparing file contents (default: 8KiB). This
-costs some additional memory but potentially reduces the amount of seek
-operations and therefore improve performance, especially with mechanic disk
-drives. Optional factor suffixes are supported, like with the *-s* option. This is mostly efficient with other filters (i.e. with *-f* or *-X*) and can be less efficient with *-top* options.
-
+*-b*, *--io-size* _size_::
+The size of read or sendfile buffer used when comparing file contents. The
+_size_ argument may be followed by the multiplicative suffixes KiB, MiB, etc.
+The "iB" is optional, e.g., "K" has the same meaning as "KiB". The default is
+8KiB for memcmp method and 1MiB for the other methods. The only memcmp method
+uses process memory for the buffer, other methods use zero-copy way and I/O
+operation is done in kernel.
 
 == ARGUMENTS
 

diff --git a/misc-utils/hardlink.c b/misc-utils/hardlink.c
index d00d1db7cedbc6dc965016c0559b1b6b11cbd139..035e3f43ec2174949d948b774b764c5e29a7bbd0 100644 (file)
--- a/misc-utils/hardlink.c
+++ b/misc-utils/hardlink.c
@@ -96,10 +96,6 @@ enum log_level {
        JLOG_VERBOSE2
 };
 
-#ifndef DEF_SCAN_BUFSIZ
-# define DEF_SCAN_BUFSIZ 8192
-#endif
-
 /**
  * struct statistic - Statistics about the file
  * @started: Whether we are post command-line processing
@@ -159,7 +155,7 @@ static struct options {
        unsigned int keep_oldest:1;
        unsigned int dry_run:1;
        uintmax_t min_size;
-       size_t bufsiz;
+       size_t io_size;
 } opts = {
        /* default setting */
        .method = "sha256",
@@ -168,8 +164,7 @@ static struct options {
        .respect_time = TRUE,
        .respect_xattrs = FALSE,
        .keep_oldest = FALSE,
-       .min_size = 1,
-       .bufsiz = DEF_SCAN_BUFSIZ
+       .min_size = 1
 };
 
 /*
@@ -830,8 +825,8 @@ static void visitor(const void *nodep, const VISIT which, const int depth)
                if (!nnodes)
                        continue;
                memsiz = (10*1024*1024)/nnodes;
-               /*                                filesiz,      readsiz,   memsiz */
-               ul_fileeq_set_size(&fileeq, master->st.st_size, 1024*1024, memsiz);
+               /*                                filesiz,      readsiz,      memsiz */
+               ul_fileeq_set_size(&fileeq, master->st.st_size, opts.io_size, memsiz);
 
                for (other = master->next; other != NULL; other = other->next) {
                        int eq;
@@ -916,7 +911,7 @@ static void __attribute__((__noreturn__)) usage(void)
        fputs(_(" -x, --exclude <regex>      regular expression to exclude files\n"), out);
        fputs(_(" -i, --include <regex>      regular expression to include files/dirs\n"), out);
        fputs(_(" -s, --minimum-size <size>  minimum size for files.\n"), out);
-       fputs(_(" -S, --buffer-size <size>   buffer size for file reading (speedup, using more RAM)\n"), out);
+       fputs(_(" -b, --io-size <size>       I/O buffer size for file reading (speedup, using more RAM)\n"), out);
        fputs(_(" -c, --content              compare only file contents, same as -pot\n"), out);
 
        fputs(USAGE_SEPARATOR, out);
@@ -933,7 +928,7 @@ static void __attribute__((__noreturn__)) usage(void)
  */
 static int parse_options(int argc, char *argv[])
 {
-       static const char optstr[] = "VhvnfpotXcmMOx:y:i:s:S:q";
+       static const char optstr[] = "VhvnfpotXcmMOx:y:i:s:b:q";
        static const struct option long_options[] = {
                {"version", no_argument, NULL, 'V'},
                {"help", no_argument, NULL, 'h'},
@@ -951,7 +946,7 @@ static int parse_options(int argc, char *argv[])
                {"include", required_argument, NULL, 'i'},
                {"method", required_argument, NULL, 'y' },
                {"minimum-size", required_argument, NULL, 's'},
-               {"buffer-size", required_argument, NULL, 'S'},
+               {"io-size", required_argument, NULL, 'b'},
                {"content", no_argument, NULL, 'c'},
                {"quiet", no_argument, NULL, 'q'},
                {NULL, 0, NULL, 0}
@@ -1020,8 +1015,8 @@ static int parse_options(int argc, char *argv[])
                case 's':
                        opts.min_size = strtosize_or_err(optarg, _("failed to parse size"));
                        break;
-               case 'S':
-                       opts.bufsiz = strtosize_or_err(optarg, _("failed to parse size"));
+               case 'b':
+                       opts.io_size = strtosize_or_err(optarg, _("failed to parse I/O size"));
                        break;
                case 'h':
                        usage();
@@ -1090,6 +1085,14 @@ int main(int argc, char *argv[])
        if (rc < 0)
                err(EXIT_FAILURE, _("failed to initialize files comparior"));
 
+       /* defautl I/O size */
+       if (!opts.io_size) {
+               if (strcmp(opts.method, "memcmp") == 0)
+                       opts.io_size = 8*1024;
+               else
+                       opts.io_size = 1024*1024;
+       }
+
        stats.started = TRUE;
 
        jlog(JLOG_VERBOSE2, _("Scanning [device/inode/links]:"));