Updated from v3 to v4:
1. in example job file, highlight 'disable_clat' and 'gtod_reduce' can not be set for file delete engine since they disable completion latency output.
2. in example job file, remove 'numjobs' option, since there is no requirement about it for file delete engine.
3. trivial message string fix.
-----Original Message-----
From: Su, Friendy
Sent: Wednesday, April 14, 2021 11:57 AM
To: fio <fio@xxxxxxxxxxxxxxx>
Cc: 'Sitsofe Wheeler' <sitsofe@xxxxxxxxx>; Kobayashi, Kento (SGC) <Kento.A.Kobayashi@xxxxxxxx>; Aoyama, Wataru (SGC) <Wataru.Aoyama@xxxxxxxx>; Su, Friendy <Friendy.Su@xxxxxxxx>
Subject: [PATCH v4 1/1] engines: add engine for file delete
This engine is to measure the performance of deleting files.
In practice, it is an important benchmark for a file system that
how quick it can release the disk space of deleted files.
Signed-off-by: friendy-su <friendy.su@xxxxxxxx>
---
HOWTO | 5 ++
Makefile | 2 +-
engines/filedelete.c | 115 +++++++++++++++++++++++++++++++
examples/filedelete-ioengine.fio | 18 +++++
fio.1 | 5 ++
5 files changed, 144 insertions(+), 1 deletion(-)
create mode 100644 engines/filedelete.c
create mode 100644 examples/filedelete-ioengine.fio
diff --git a/HOWTO b/HOWTO
index 2788670d..e6078c5f 100644
--- a/HOWTO
+++ b/HOWTO
@@ -2055,6 +2055,11 @@ I/O engine
and 'nrfiles', so that files will be created.
This engine is to measure file lookup and meta data access.
+ **filedelete**
+ Simply delete the files by unlink() and do no I/O to them. You need to set 'filesize'
+ and 'nrfiles', so that the files will be created.
+ This engine is to measure file delete.
+
**libpmem**
Read and write using mmap I/O to a file on a filesystem
mounted with DAX on a persistent memory device through the PMDK
diff --git a/Makefile b/Makefile
index fce3d0d1..ba027b2e 100644
--- a/Makefile
+++ b/Makefile
@@ -51,7 +51,7 @@ SOURCE := $(sort $(patsubst $(SRCDIR)/%,%,$(wildcard $(SRCDIR)/crc/*.c)) \
pshared.c options.c \
smalloc.c filehash.c profile.c debug.c engines/cpu.c \
engines/mmap.c engines/sync.c engines/null.c engines/net.c \
- engines/ftruncate.c engines/filecreate.c engines/filestat.c \
+ engines/ftruncate.c engines/filecreate.c engines/filestat.c engines/filedelete.c \
server.c client.c iolog.c backend.c libfio.c flow.c cconv.c \
gettime-thread.c helpers.c json.c idletime.c td_error.c \
profiles/tiobench.c profiles/act.c io_u_queue.c filelock.c \
diff --git a/engines/filedelete.c b/engines/filedelete.c
new file mode 100644
index 00000000..64c58639
--- /dev/null
+++ b/engines/filedelete.c
@@ -0,0 +1,115 @@
+/*
+ * file delete engine
+ *
+ * IO engine that doesn't do any IO, just delete files and track the latency
+ * of the file deletion.
+ */
+#include <stdio.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include "../fio.h"
+
+struct fc_data {
+ enum fio_ddir stat_ddir;
+};
+
+static int delete_file(struct thread_data *td, struct fio_file *f)
+{
+ struct timespec start;
+ int do_lat = !td->o.disable_lat;
+ int ret;
+
+ dprint(FD_FILE, "fd delete %s\n", f->file_name);
+
+ if (f->filetype != FIO_TYPE_FILE) {
+ log_err("fio: only files are supported\n");
+ return 1;
+ }
+ if (!strcmp(f->file_name, "-")) {
+ log_err("fio: can't read/write to stdin/out\n");
+ return 1;
+ }
+
+ if (do_lat)
+ fio_gettime(&start, NULL);
+
+ ret = unlink(f->file_name);
+
+ if (ret == -1) {
+ char buf[FIO_VERROR_SIZE];
+ int e = errno;
+
+ snprintf(buf, sizeof(buf), "delete(%s)", f->file_name);
+ td_verror(td, e, buf);
+ return 1;
+ }
+
+ if (do_lat) {
+ struct fc_data *data = td->io_ops_data;
+ uint64_t nsec;
+
+ nsec = ntime_since_now(&start);
+ add_clat_sample(td, data->stat_ddir, nsec, 0, 0, 0);
+ }
+
+ return 0;
+}
+
+
+static enum fio_q_status queue_io(struct thread_data *td, struct io_u fio_unused *io_u)
+{
+ return FIO_Q_COMPLETED;
+}
+
+static int init(struct thread_data *td)
+{
+ struct fc_data *data;
+
+ data = calloc(1, sizeof(*data));
+
+ if (td_read(td))
+ data->stat_ddir = DDIR_READ;
+ else if (td_write(td))
+ data->stat_ddir = DDIR_WRITE;
+
+ td->io_ops_data = data;
+ return 0;
+}
+
+static int delete_invalidate(struct thread_data *td, struct fio_file *f)
+{
+ /* do nothing because file not opened */
+ return 0;
+}
+
+static void cleanup(struct thread_data *td)
+{
+ struct fc_data *data = td->io_ops_data;
+
+ free(data);
+}
+
+static struct ioengine_ops ioengine = {
+ .name = "filedelete",
+ .version = FIO_IOOPS_VERSION,
+ .init = init,
+ .invalidate = delete_invalidate,
+ .cleanup = cleanup,
+ .queue = queue_io,
+ .get_file_size = generic_get_file_size,
+ .open_file = delete_file,
+ .flags = FIO_SYNCIO | FIO_FAKEIO |
+ FIO_NOSTATS | FIO_NOFILEHASH,
+};
+
+static void fio_init fio_filedelete_register(void)
+{
+ register_ioengine(&ioengine);
+}
+
+static void fio_exit fio_filedelete_unregister(void)
+{
+ unregister_ioengine(&ioengine);
+}
diff --git a/examples/filedelete-ioengine.fio b/examples/filedelete-ioengine.fio
new file mode 100644
index 00000000..3c0028f9
--- /dev/null
+++ b/examples/filedelete-ioengine.fio
@@ -0,0 +1,18 @@
+# Example filedelete job
+
+# 'filedelete' engine only do 'unlink(filename)', file will not be open().
+# 'filesize' must be set, then files will be created at setup stage.
+# 'unlink' is better set to 0, since the file is deleted in measurement.
+# the options disabled completion latency output such as 'disable_clat' and 'gtod_reduce' must not set.
+[global]
+ioengine=filedelete
+filesize=4k
+nrfiles=200
+unlink=0
+
+[t0]
+[t1]
+[t2]
+[t3]
+[t4]
+[t5]
diff --git a/fio.1 b/fio.1
index f959e00d..c59a8002 100644
--- a/fio.1
+++ b/fio.1
@@ -1847,6 +1847,11 @@ Simply do stat() and do no I/O to the file. You need to set 'filesize'
and 'nrfiles', so that files will be created.
This engine is to measure file lookup and meta data access.
.TP
+.B filedelete
+Simply delete files by unlink() and do no I/O to the file. You need to set 'filesize'
+and 'nrfiles', so that files will be created.
+This engine is to measure file delete.
+.TP
.B libpmem
Read and write using mmap I/O to a file on a filesystem
mounted with DAX on a persistent memory device through the PMDK
--
2.17.1
