diff options
| author | Bob Peterson <rpeterso@redhat.com> | 2012-07-19 08:12:40 -0400 |
|---|---|---|
| committer | Steven Whitehouse <swhiteho@redhat.com> | 2012-07-19 14:51:08 +0100 |
| commit | 8e2e00473598dd5379d8408cb974dade000acafc (patch) | |
| tree | 1f7bfdf0d07b6c0315bbd11ffee174742d66a459 /fs/gfs2/rgrp.h | |
| parent | 294f2ad5a545eb71d397623743ddd8201131bdad (diff) | |
GFS2: Reduce file fragmentation
This patch reduces GFS2 file fragmentation by pre-reserving blocks. The
resulting improved on disk layout greatly speeds up operations in cases
which would have resulted in interlaced allocation of blocks previously.
A typical example of this is 10 parallel dd processes, each writing to a
file in a common dirctory.
The implementation uses an rbtree of reservations attached to each
resource group (and each inode).
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/gfs2/rgrp.h')
| -rw-r--r-- | fs/gfs2/rgrp.h | 31 |
1 files changed, 30 insertions, 1 deletions
diff --git a/fs/gfs2/rgrp.h b/fs/gfs2/rgrp.h index 5d8314dbc899..ca6e26729b86 100644 --- a/fs/gfs2/rgrp.h +++ b/fs/gfs2/rgrp.h @@ -13,6 +13,14 @@ #include <linux/slab.h> #include <linux/uaccess.h> +/* Since each block in the file system is represented by two bits in the + * bitmap, one 64-bit word in the bitmap will represent 32 blocks. + * By reserving 32 blocks at a time, we can optimize / shortcut how we search + * through the bitmaps by looking a word at a time. + */ +#define RGRP_RSRV_MINBYTES 8 +#define RGRP_RSRV_MINBLKS ((u32)(RGRP_RSRV_MINBYTES * GFS2_NBBY)) + struct gfs2_rgrpd; struct gfs2_sbd; struct gfs2_holder; @@ -29,6 +37,8 @@ extern void gfs2_free_clones(struct gfs2_rgrpd *rgd); extern int gfs2_rgrp_go_lock(struct gfs2_holder *gh); extern void gfs2_rgrp_go_unlock(struct gfs2_holder *gh); +extern struct gfs2_alloc *gfs2_alloc_get(struct gfs2_inode *ip); + extern int gfs2_inplace_reserve(struct gfs2_inode *ip, u32 requested); extern void gfs2_inplace_release(struct gfs2_inode *ip); @@ -36,6 +46,7 @@ extern int gfs2_alloc_blocks(struct gfs2_inode *ip, u64 *bn, unsigned int *n, bool dinode, u64 *generation); extern int gfs2_rs_alloc(struct gfs2_inode *ip); +extern void gfs2_rs_deltree(struct gfs2_blkreserv *rs); extern void gfs2_rs_delete(struct gfs2_inode *ip); extern void __gfs2_free_blocks(struct gfs2_inode *ip, u64 bstart, u32 blen, int meta); extern void gfs2_free_meta(struct gfs2_inode *ip, u64 bstart, u32 blen); @@ -62,7 +73,7 @@ extern int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset, const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed); extern int gfs2_fitrim(struct file *filp, void __user *argp); -/* This is how to tell if a reservation is "inplace" reserved: */ +/* This is how to tell if a multi-block reservation is "inplace" reserved: */ static inline int gfs2_mb_reserved(struct gfs2_inode *ip) { if (ip->i_res && ip->i_res->rs_requested) @@ -70,4 +81,22 @@ static inline int gfs2_mb_reserved(struct gfs2_inode *ip) return 0; } +/* This is how to tell if a multi-block reservation is in the rgrp tree: */ +static inline int gfs2_rs_active(struct gfs2_blkreserv *rs) +{ + if (rs && rs->rs_bi) + return 1; + return 0; +} + +static inline u32 gfs2_bi2rgd_blk(const struct gfs2_bitmap *bi, u32 blk) +{ + return (bi->bi_start * GFS2_NBBY) + blk; +} + +static inline u64 gfs2_rs_startblk(const struct gfs2_blkreserv *rs) +{ + return gfs2_bi2rgd_blk(rs->rs_bi, rs->rs_biblk) + rs->rs_rgd->rd_data0; +} + #endif /* __RGRP_DOT_H__ */ |