2013-07-02 05:46:22

by majianpeng

Subject: [PATCH 1/3] mds: update atime if client can read.

Now, update atime only for CEPH_CAP_FILE_EXCL.Change this if
CEPH_CAP_FILE_RD.

Signed-off-by: Jianpeng Ma <[email protected]>
---
src/mds/Locker.cc | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/mds/Locker.cc b/src/mds/Locker.cc
index 30e014a..58f953f 100644
--- a/src/mds/Locker.cc
+++ b/src/mds/Locker.cc
@@ -2676,8 +2676,9 @@ void Locker::_do_snap_update(CInode *in, snapid_t snap, int dirty, snapid_t foll
void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *pi)
{
// file
+ utime_t atime = m->get_atime();
+
if (dirty & (CEPH_CAP_FILE_EXCL|CEPH_CAP_FILE_WR)) {
- utime_t atime = m->get_atime();
utime_t mtime = m->get_mtime();
utime_t ctime = m->get_ctime();
uint64_t size = m->get_size();
@@ -2700,11 +2701,7 @@ void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *
pi->size = size;
pi->rstat.rbytes = size;
}
- if ((dirty & CEPH_CAP_FILE_EXCL) && atime != pi->atime) {
- dout(7) << " atime " << pi->atime << " -> " << atime
- << " for " << *in << dendl;
- pi->atime = atime;
- }
+
if ((dirty & CEPH_CAP_FILE_EXCL) &&
ceph_seq_cmp(pi->time_warp_seq, m->get_time_warp_seq()) < 0) {
dout(7) << " time_warp_seq " << pi->time_warp_seq << " -> " << m->get_time_warp_seq()
@@ -2712,6 +2709,12 @@ void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *
pi->time_warp_seq = m->get_time_warp_seq();
}
}
+
+ if ((dirty & CEPH_CAP_FILE_RD) && atime > pi->atime) {
+ dout(7) << " atime " << pi->atime << " -> " << atime
+ << " for " << *in << dendl;
+ pi->atime = atime;
+ }
// auth
if (dirty & CEPH_CAP_AUTH_EXCL) {
if (m->head.uid != pi->uid) {
--
1.8.3.rc1.44.gb387c77
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2013-07-02 16:48:20

by Sage Weil

Subject: Re: [PATCH 1/3] mds: update atime if client can read.

On Tue, 2 Jul 2013, majianpeng wrote:
> Now, update atime only for CEPH_CAP_FILE_EXCL.Change this if
> CEPH_CAP_FILE_RD.

Can we introduce a global config optoin (bool mds_atime in
common/config_opts.h, maybe) so that users can turn this off? And/or add
a 'relatime' option? More users won't want this as it is very expensive
to maintain this extra level of metadata.

That aside, this approach looks right to me. :)

Thanks!
sage


>
> Signed-off-by: Jianpeng Ma <[email protected]>
> ---
> src/mds/Locker.cc | 15 +++++++++------
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/src/mds/Locker.cc b/src/mds/Locker.cc
> index 30e014a..58f953f 100644
> --- a/src/mds/Locker.cc
> +++ b/src/mds/Locker.cc
> @@ -2676,8 +2676,9 @@ void Locker::_do_snap_update(CInode *in, snapid_t snap, int dirty, snapid_t foll
> void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *pi)
> {
> // file
> + utime_t atime = m->get_atime();
> +
> if (dirty & (CEPH_CAP_FILE_EXCL|CEPH_CAP_FILE_WR)) {
> - utime_t atime = m->get_atime();
> utime_t mtime = m->get_mtime();
> utime_t ctime = m->get_ctime();
> uint64_t size = m->get_size();
> @@ -2700,11 +2701,7 @@ void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *
> pi->size = size;
> pi->rstat.rbytes = size;
> }
> - if ((dirty & CEPH_CAP_FILE_EXCL) && atime != pi->atime) {
> - dout(7) << " atime " << pi->atime << " -> " << atime
> - << " for " << *in << dendl;
> - pi->atime = atime;
> - }
> +
> if ((dirty & CEPH_CAP_FILE_EXCL) &&
> ceph_seq_cmp(pi->time_warp_seq, m->get_time_warp_seq()) < 0) {
> dout(7) << " time_warp_seq " << pi->time_warp_seq << " -> " << m->get_time_warp_seq()
> @@ -2712,6 +2709,12 @@ void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *
> pi->time_warp_seq = m->get_time_warp_seq();
> }
> }
> +
> + if ((dirty & CEPH_CAP_FILE_RD) && atime > pi->atime) {
> + dout(7) << " atime " << pi->atime << " -> " << atime
> + << " for " << *in << dendl;
> + pi->atime = atime;
> + }
> // auth
> if (dirty & CEPH_CAP_AUTH_EXCL) {
> if (m->head.uid != pi->uid) {
> --
> 1.8.3.rc1.44.gb387c77
>

2013-07-03 01:25:46

by majianpeng

Subject: Re: Re: [PATCH 1/3] mds: update atime if client can read.

>On Tue, 2 Jul 2013, majianpeng wrote:
>> Now, update atime only for CEPH_CAP_FILE_EXCL.Change this if
>> CEPH_CAP_FILE_RD.
>
>Can we introduce a global config optoin (bool mds_atime in
>common/config_opts.h, maybe) so that users can turn this off? And/or add
>a 'relatime' option? More users won't want this as it is very expensive
>to maintain this extra level of metadata.
>
I don't know other client except cephfs.So the patch is from the view of using cephfs.
For cephfs,we can mount using 'noatime' to indicate don't update atime.
But for the other client, i don't know.
I think this should controled by client not server.

>That aside, this approach looks right to me. :)
>
>Thanks!
>sage
>
>
> >
>> Signed-off-by: Jianpeng Ma <[email protected]>
>> ---
>> src/mds/Locker.cc | 15 +++++++++------
>> 1 file changed, 9 insertions(+), 6 deletions(-)
>>
>> diff --git a/src/mds/Locker.cc b/src/mds/Locker.cc
>> index 30e014a..58f953f 100644
>> --- a/src/mds/Locker.cc
>> +++ b/src/mds/Locker.cc
>> @@ -2676,8 +2676,9 @@ void Locker::_do_snap_update(CInode *in, snapid_t snap, int dirty, snapid_t foll
>> void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *pi)
>> {
>> // file
>> + utime_t atime = m->get_atime();
>> +
>> if (dirty & (CEPH_CAP_FILE_EXCL|CEPH_CAP_FILE_WR)) {
>> - utime_t atime = m->get_atime();
>> utime_t mtime = m->get_mtime();
>> utime_t ctime = m->get_ctime();
>> uint64_t size = m->get_size();
>> @@ -2700,11 +2701,7 @@ void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *
>> pi->size = size;
>> pi->rstat.rbytes = size;
>> }
>> - if ((dirty & CEPH_CAP_FILE_EXCL) && atime != pi->atime) {
>> - dout(7) << " atime " << pi->atime << " -> " << atime
>> - << " for " << *in << dendl;
>> - pi->atime = atime;
>> - }
>> +
>> if ((dirty & CEPH_CAP_FILE_EXCL) &&
>> ceph_seq_cmp(pi->time_warp_seq, m->get_time_warp_seq()) < 0) {
>> dout(7) << " time_warp_seq " << pi->time_warp_seq << " -> " << m->get_time_warp_seq()
>> @@ -2712,6 +2709,12 @@ void Locker::_update_cap_fields(CInode *in, int dirty, MClientCaps *m, inode_t *
>> pi->time_warp_seq = m->get_time_warp_seq();
>> }
>> }
>> +
>> + if ((dirty & CEPH_CAP_FILE_RD) && atime > pi->atime) {
>> + dout(7) << " atime " << pi->atime << " -> " << atime
>> + << " for " << *in << dendl;
>> + pi->atime = atime;
>> + }
>> // auth
>> if (dirty & CEPH_CAP_AUTH_EXCL) {
>> if (m->head.uid != pi->uid) {
>> --
>> 1.8.3.rc1.44.gb387c77
>> ????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m????????????I?