Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-we0-f174.google.com ([74.125.82.174]:56047 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751246Ab2BNPoL convert rfc822-to-8bit (ORCPT ); Tue, 14 Feb 2012 10:44:11 -0500 Received: by werb13 with SMTP id b13so51394wer.19 for ; Tue, 14 Feb 2012 07:44:10 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <4F3A29E8.5000904@tonian.com> References: <1328721042-9335-1-git-send-email-dros@netapp.com> <1CFC0549-DFAC-4530-A3A5-876DDAE8C5DE@oracle.com> <4F38C443.2060307@tonian.com> <4F3A29E8.5000904@tonian.com> Date: Tue, 14 Feb 2012 10:44:07 -0500 Message-ID: Subject: Re: [PATCH] RFC: NFS - filelayout DS rpc mountstats support From: Andy Adamson To: Benny Halevy Cc: "Adamson, Dros" , Chuck Lever , "Myklebust, Trond" , linux-nfs Content-Type: text/plain; charset=windows-1252 Sender: linux-nfs-owner@vger.kernel.org List-ID: I have an early patch set that prints session stats for MDS and for DS. The DS pnfs_layoutdriver_type interface for session stats takes the same arguments as the RPC iostats interface, a seq_file* and a struct nfs4_deviceid_node. >>>>>> + void (*ds_rpc_print_iostats) (struct seq_file *, >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct nfs4_deviceid_node *); We can use the same interface for RPC and session stats. I suggest you rename this to "ds_stats" and add an enum type to identify which stats are being requested. -->Andy On Tue, Feb 14, 2012 at 4:31 AM, Benny Halevy wrote: > On 2012-02-13 19:58, Adamson, Dros wrote: >> >> On Feb 13, 2012, at 3:05 AM, Benny Halevy wrote: >> >>> Sorry for the late response. >>> >>> On 2012-02-08 23:04, Adamson, Dros wrote: >>>> >>>> On Feb 8, 2012, at 12:26 PM, Chuck Lever wrote: >>>> >>>>> Hi- >>>>> >>>>> On Feb 8, 2012, at 12:10 PM, Weston Andros Adamson wrote: >>>>> >>>>>> The per-op stats displayed in /self/proc/mountstats are collected in the sunrpc >>>>> >>>>> You mean /proc/self/mountstats here. >>>> >>>> oops! >>>> >>>>> >>>>>> layer and are collected per rpc_client. ?This has worked for nfs thus far >>>>>> since only one nfs_client was ever associated with a mountpoint, but with >>>>>> NFS4.1+PNFS+filelayout an nfs mount can have more than one nfs_client. >>>>>> >>>>>> This can be seen with a pnfs mount where no data server is the same as the MDS - >>>>>> all reads, writes and commits will never make it into the current mountstats >>>>>> output. >>>>>> >>>>>> I took the approach of keeping the stats from the MDS and DSs separate in the >>>>>> /proc/self/mountstats output to avoid doing too much in the kernel, and to >>>>>> expose the fact that these stats are from separate connections (maybe for later >>>>>> use). >>>>>> >>>>>> This method has issues: >>>>>> >>>>>> 1) even changing the "statvers" of mountstats doesn't stop the userland >>>>>> ?mountstats(8) from trying to parse this output -- and it does so >>>>>> ?incorrectly. >>>>> >>>>> User land is broken then. ?:-) >>>> >>>> Agreed! >>>> >>>>> >>>>>> 2) when using DS multipath this method fails to count operations that happened >>>>>> ?on a different path to the same DS (after a failure). >>>> >>>> I should have noted that this isn't a problem yet because I haven't submitted the multipath failover patches :) >>>> >>>>>> >>>>>> 3) currently this will display stats twice when DS == MDS. >>>>> >>>>> Why is this case hard to detect in the kernel or in mountstats? >>>> >>>> Not hard, just an issue with the current patch. >>>> >>>>> >>>>>> >>>>>> So... What should I do here? >>>>>> >>>>>> A different approach is to add support in net/sunrpc to specify a "parent" >>>>>> stat structure so that operations on DS nfs_clients bump stats on >>>>>> the main nfs_server->nfs_client->rpc_client. ?This would take care of all the >>>>>> issues with the current patch, but seems like a hack. >>>>> >>>>> Is this the same as displaying all data in one set of stats? >>>> >>>> Yes >>>> >>>>> >>>>> Seems like that might be the best next step, then we can split up the MDS and DS stats at some later point. >>> >>> Splitting up the MDS/DS stats is important to tell when DS I/O is being >>> done and how effective it is. >>> >>> Benny >>> >> >> Agreed! ?It just can't go into mountstats right away (due to statsvers= not being interpreted in mountstats(8)). ?I'll make a second patch on top of my mountstats changes to add per-DS stats in /proc/fs/nfsfs/ and we can figure out if we want to add it to mountstats later. >> >> Does this sound OK? > > Absolutely. ?Thanks! > > Benny > >> >> -dros >> >>>> >>>> Ok, I'll try to do that. >>>> >>>> Any advice on how to handle the "xprt: ?" line? ?Obviously the different underlying rpc_clients will have different values. ?I'd have to look at mountstats(8) some more, but I *think* we could just make it a comma separated list. >>>> >>>> For the 'next step', we can use this patch - we just need to figure out where it should go. ?Do we keep it in /proc/self/mountstats? ?I think because of problem #2 we might want to move them out to somewhere in /proc/fs/nfsfs/ along with other per-DS statistics. >>>> >>>>> >>>>>> One task that seems like a good thing to do is to fix mountstats(8) to respect >>>>>> the "statsvers" value. >>>>> >>>>> Agree. >>>> >>>> I'll do this first. >>>> >>>> Thanks Chuck! >>>> >>>> -dros >>>> >>>>> >>>>>> >>>>>> Thoughts? >>>>>> --- >>>>>> >>>>>> I cleaned up this patch, but I still have reservations (noted in commit message) >>>>>> >>>>>> fs/nfs/nfs4filelayout.c ? ?| ? 23 +++++++++++++++++++++++ >>>>>> fs/nfs/pnfs.h ? ? ? ? ? ? ?| ? 20 ++++++++++++++++++++ >>>>>> fs/nfs/pnfs_dev.c ? ? ? ? ?| ? 25 +++++++++++++++++++++++++ >>>>>> fs/nfs/super.c ? ? ? ? ? ? | ? ?1 + >>>>>> include/linux/nfs_iostat.h | ? ?2 +- >>>>>> 5 files changed, 70 insertions(+), 1 deletions(-) >>>>>> >>>>>> diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c >>>>>> index 79be7ac..9410fd0 100644 >>>>>> --- a/fs/nfs/nfs4filelayout.c >>>>>> +++ b/fs/nfs/nfs4filelayout.c >>>>>> @@ -33,6 +33,8 @@ >>>>>> #include >>>>>> #include >>>>>> >>>>>> +#include >>>>>> + >>>>>> #include "internal.h" >>>>>> #include "nfs4filelayout.h" >>>>>> >>>>>> @@ -918,6 +920,26 @@ filelayout_free_deveiceid_node(struct nfs4_deviceid_node *d) >>>>>> ? nfs4_fl_free_deviceid(container_of(d, struct nfs4_file_layout_dsaddr, id_node)); >>>>>> } >>>>>> >>>>>> +static void >>>>>> +filelayout_rpc_print_iostats(struct seq_file *m, struct nfs4_deviceid_node *d) >>>>>> +{ >>>>>> + struct nfs4_file_layout_dsaddr *dsaddr; >>>>>> + struct nfs4_pnfs_ds *ds; >>>>>> + u32 i; >>>>>> + >>>>>> + dsaddr = container_of(d, struct nfs4_file_layout_dsaddr, id_node); >>>>>> + >>>>>> + for (i = 0; i < dsaddr->ds_num; i++) { >>>>>> + ? ? ? ? ds = dsaddr->ds_list[i]; >>>>>> + >>>>>> + ? ? ? ? if (ds && ds->ds_clp) { >>>>>> + ? ? ? ? ? ? ? ? seq_printf(m, " ?pnfs dataserver %s\n", >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ?ds->ds_remotestr); >>>>>> + ? ? ? ? ? ? ? ? rpc_print_iostats(m, ds->ds_clp->cl_rpcclient); >>>>>> + ? ? ? ? } >>>>>> + } >>>>>> +} >>>>>> + >>>>>> static struct pnfs_layoutdriver_type filelayout_type = { >>>>>> ? .id ? ? ? ? ? ? ? ? ? ? = LAYOUT_NFSV4_1_FILES, >>>>>> ? .name ? ? ? ? ? ? ? ? ? = "LAYOUT_NFSV4_1_FILES", >>>>>> @@ -932,6 +954,7 @@ static struct pnfs_layoutdriver_type filelayout_type = { >>>>>> ? .read_pagelist ? ? ? ? ?= filelayout_read_pagelist, >>>>>> ? .write_pagelist ? ? ? ? = filelayout_write_pagelist, >>>>>> ? .free_deviceid_node ? ? = filelayout_free_deveiceid_node, >>>>>> + .ds_rpc_print_iostats ? = filelayout_rpc_print_iostats, >>>>>> }; >>>>>> >>>>>> static int __init nfs4filelayout_init(void) >>>>>> diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h >>>>>> index 53d593a..0a5e020 100644 >>>>>> --- a/fs/nfs/pnfs.h >>>>>> +++ b/fs/nfs/pnfs.h >>>>>> @@ -119,6 +119,9 @@ struct pnfs_layoutdriver_type { >>>>>> ? void (*encode_layoutcommit) (struct pnfs_layout_hdr *layoutid, >>>>>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?struct xdr_stream *xdr, >>>>>> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?const struct nfs4_layoutcommit_args *args); >>>>>> + >>>>>> + void (*ds_rpc_print_iostats) (struct seq_file *, >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct nfs4_deviceid_node *); >>>>>> }; >>>>>> >>>>>> struct pnfs_layout_hdr { >>>>>> @@ -239,6 +242,10 @@ void nfs4_init_deviceid_node(struct nfs4_deviceid_node *, >>>>>> struct nfs4_deviceid_node *nfs4_insert_deviceid_node(struct nfs4_deviceid_node *); >>>>>> bool nfs4_put_deviceid_node(struct nfs4_deviceid_node *); >>>>>> void nfs4_deviceid_purge_client(const struct nfs_client *); >>>>>> +void nfs4_deviceid_rpc_print_iostats(struct seq_file *seq, >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?const struct nfs_client *clp, >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?const struct pnfs_layoutdriver_type *ld); >>>>>> + >>>>>> >>>>>> static inline int lo_fail_bit(u32 iomode) >>>>>> { >>>>>> @@ -328,6 +335,14 @@ static inline int pnfs_return_layout(struct inode *ino) >>>>>> ? return 0; >>>>>> } >>>>>> >>>>>> +static inline void >>>>>> +pnfs_rpc_print_iostats(struct seq_file *m, struct nfs_server *nfss) >>>>>> +{ >>>>>> + if (!pnfs_enabled_sb(nfss)) >>>>>> + ? ? ? ? return; >>>>>> + nfs4_deviceid_rpc_print_iostats(m, nfss->nfs_client, >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? nfss->pnfs_curr_ld); >>>>>> +} >>>>>> #else ?/* CONFIG_NFS_V4_1 */ >>>>>> >>>>>> static inline void pnfs_destroy_all_layouts(struct nfs_client *clp) >>>>>> @@ -429,6 +444,11 @@ static inline int pnfs_layoutcommit_inode(struct inode *inode, bool sync) >>>>>> static inline void nfs4_deviceid_purge_client(struct nfs_client *ncl) >>>>>> { >>>>>> } >>>>>> + >>>>>> +static inline void >>>>>> +pnfs_rpc_print_iostats(struct seq_file *m, struct nfs_server *nfss) >>>>>> +{ >>>>>> +} >>>>>> #endif /* CONFIG_NFS_V4_1 */ >>>>>> >>>>>> #endif /* FS_NFS_PNFS_H */ >>>>>> diff --git a/fs/nfs/pnfs_dev.c b/fs/nfs/pnfs_dev.c >>>>>> index 4f359d2..277de87 100644 >>>>>> --- a/fs/nfs/pnfs_dev.c >>>>>> +++ b/fs/nfs/pnfs_dev.c >>>>>> @@ -115,6 +115,31 @@ nfs4_find_get_deviceid(const struct pnfs_layoutdriver_type *ld, >>>>>> } >>>>>> EXPORT_SYMBOL_GPL(nfs4_find_get_deviceid); >>>>>> >>>>>> + >>>>>> +void >>>>>> +nfs4_deviceid_rpc_print_iostats(struct seq_file *seq, >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? const struct nfs_client *clp, >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? const struct pnfs_layoutdriver_type *ld) >>>>>> +{ >>>>>> + struct nfs4_deviceid_node *d; >>>>>> + struct hlist_node *n; >>>>>> + long h; >>>>>> + >>>>>> + if (!ld->ds_rpc_print_iostats) >>>>>> + ? ? ? ? return; >>>>>> + >>>>>> + rcu_read_lock(); >>>>>> + for (h = 0; h < NFS4_DEVICE_ID_HASH_SIZE; h++) { >>>>>> + ? ? ? ? hlist_for_each_entry_rcu(d, n, &nfs4_deviceid_cache[h], node) >>>>>> + ? ? ? ? ? ? ? ? if (d->ld == ld && d->nfs_client == clp) { >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? if (atomic_read(&d->ref)) >>>>>> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ld->ds_rpc_print_iostats(seq, d); >>>>>> + ? ? ? ? ? ? ? ? } >>>>>> + } >>>>>> + rcu_read_unlock(); >>>>>> +} >>>>>> +EXPORT_SYMBOL_GPL(nfs4_deviceid_rpc_print_iostats); >>>>>> + >>>>>> /* >>>>>> * Remove a deviceid from cache >>>>>> * >>>>>> diff --git a/fs/nfs/super.c b/fs/nfs/super.c >>>>>> index d18a90b..453e496 100644 >>>>>> --- a/fs/nfs/super.c >>>>>> +++ b/fs/nfs/super.c >>>>>> @@ -871,6 +871,7 @@ static int nfs_show_stats(struct seq_file *m, struct dentry *root) >>>>>> ? seq_printf(m, "\n"); >>>>>> >>>>>> ? rpc_print_iostats(m, nfss->client); >>>>>> + pnfs_rpc_print_iostats(m, nfss); >>>>>> >>>>>> ? return 0; >>>>>> } >>>>>> diff --git a/include/linux/nfs_iostat.h b/include/linux/nfs_iostat.h >>>>>> index 8866bb3..7fe4605 100644 >>>>>> --- a/include/linux/nfs_iostat.h >>>>>> +++ b/include/linux/nfs_iostat.h >>>>>> @@ -21,7 +21,7 @@ >>>>>> #ifndef _LINUX_NFS_IOSTAT >>>>>> #define _LINUX_NFS_IOSTAT >>>>>> >>>>>> -#define NFS_IOSTAT_VERS ? ? ? ? ?"1.0" >>>>>> +#define NFS_IOSTAT_VERS ? ? ? ? ?"2.0" >>>>>> >>>>>> /* >>>>>> * NFS byte counters >>>>>> -- >>>>>> 1.7.4.4 >>>>>> >>>>> >>>>> -- >>>>> Chuck Lever >>>>> chuck[dot]lever[at]oracle[dot]com >>>>> >>>>> >>>>> >>>>> >>>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at ?http://vger.kernel.org/majordomo-info.html >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at ?http://vger.kernel.org/majordomo-info.html