Using TMPFS for /tmp and /var/run?
Gleb Kurtsou
gleb.kurtsou at gmail.com
Thu Apr 5 07:43:09 UTC 2012
On (04/04/2012 06:38), David Wolfskill wrote:
> On Wed, Apr 04, 2012 at 12:50:35PM +0300, Gleb Kurtsou wrote:
> > ...
> > tmpfs-32bit-size_max.patch.txt should fix the problem. I don't have i386
> > installations to test it myself.
> >
> > Do you run PAE kernel? Could you try filling up /tmp at least to 10g.
> > ...
>
> After updating source to r233868, applying the patch, then updating,
> here are the results of my testing so far (not using PAE).
>
> Summary: as before, I believe that the patch didn't hurt anything, but
> it also doesn't restrict the usable size of /tmp to the specified size
> (from /etc/fstab):
>
I've checked on i386 and patch worked as expected, but it required
previous patch. I've combined both patches. Could you try it.
Thanks,
Gleb.
>
> Script started on Wed Apr 4 06:23:25 2012
>
> g1-227(10.0-C)[1] _do
> uid=0(root) gid=0(wheel) groups=0(wheel),5(operator)
> /dev/ada0s2a on / (ufs, local, soft-updates)
> devfs on /dev (devfs, local, multilabel)
> tmpfs on /tmp (tmpfs, local)
> /dev/ada0s2d on /usr (ufs, local, soft-updates)
> /dev/ada0s4e on /var (ufs, local, soft-updates)
> /dev/ada0s4g on /common (ufs, local, soft-updates)
> fdescfs on /dev/fd (fdescfs)
> FreeBSD g1-227.catwhisker.org 10.0-CURRENT FreeBSD 10.0-CURRENT #2 233868M: Wed Apr 4 06:02:25 PDT 2012 root at g1-227.catwhisker.org:/usr/obj/usr/src/sys/CANARY i386
> Wed Apr 4 06:23:27 PDT 2012
> >>> Removing old libraries
> Please be sure no application still uses those libraries, else you
> can not start such an application. Consult UPDATING for more
> information regarding how to cope with the removal/revision bump
> of a specific library.
> >>> Old libraries removed
> Wed Apr 4 06:23:28 PDT 2012
> g1-227(10.0-C)[2] exit
>
> Script done on Wed Apr 4 06:23:29 2012
> Script started on Wed Apr 4 06:23:35 2012
>
> g1-227(10.0-C)[1] df -hi /tmp
> Filesystem Size Used Avail Capacity iused ifree %iused Mounted on
> tmpfs 23G 12k 23G 0% 17 2.1G 0% /tmp
> g1-227(10.0-C)[2] grep tmpfs /etc/fstab
> # tmpfs /tmp tmpfs rw,size=2147483648 0 0
> tmpfs /tmp tmpfs rw,size=8g 0 0
>
> g1-227(10.0-C)[3] ls -lhT /bkp/tmp/test
> -rw-r--r-- 1 david wheel 8.0G Mar 25 10:42:49 2012 /bkp/tmp/test
> g1-227(10.0-C)[4] dd bs=1m if=!$ of=/tmp/test
> dd bs=1m if=/bkp/tmp/test of=/tmp/test
> 8192+0 records in
> 8192+0 records out
> 8589934592 bytes transferred in 186.178099 secs (46138266 bytes/sec)
> g1-227(10.0-C)[5] df -hi /tmp
> Filesystem Size Used Avail Capacity iused ifree %iused Mounted on
> tmpfs 23G 8.0G 15G 35% 18 2.1G 0% /tmp
> g1-227(10.0-C)[6] dd bs=1m if=/bkp/tmp/test of=/tmp/test1
> 8192+0 records in
> 8192+0 records out
> 8589934592 bytes transferred in 220.254916 secs (38999968 bytes/sec)
> g1-227(10.0-C)[7] df -hi /tmp
> Filesystem Size Used Avail Capacity iused ifree %iused Mounted on
> tmpfs 23G 16G 7.0G 70% 19 2.1G 0% /tmp
> g1-227(10.0-C)[8] exit
>
> Script done on Wed Apr 4 06:33:12 2012
> g1-227(10.0-C)[5]
>
>
> Peace,
> david
> --
> David H. Wolfskill david at catwhisker.org
> Depriving a girl or boy of an opportunity for education is evil.
>
> See http://www.catwhisker.org/~david/publickey.gpg for my public key.
-------------- next part --------------
diff --git a/sys/fs/tmpfs/tmpfs.h b/sys/fs/tmpfs/tmpfs.h
index efa7c6d..3fc72ab 100644
--- a/sys/fs/tmpfs/tmpfs.h
+++ b/sys/fs/tmpfs/tmpfs.h
@@ -337,11 +337,10 @@ struct tmpfs_mount {
* system, set during mount time. This variable must never be
* used directly as it may be bigger than the current amount of
* free memory; in the extreme case, it will hold the SIZE_MAX
- * value. Instead, use the TMPFS_PAGES_MAX macro. */
+ * value. */
size_t tm_pages_max;
- /* Number of pages in use by the file system. Cannot be bigger
- * than the value returned by TMPFS_PAGES_MAX in any case. */
+ /* Number of pages in use by the file system. */
size_t tm_pages_used;
/* Pointer to the node representing the root directory of this
@@ -486,58 +485,32 @@ int tmpfs_truncate(struct vnode *, off_t);
* Memory management stuff.
*/
-/* Amount of memory pages to reserve for the system (e.g., to not use by
+/*
+ * Amount of memory pages to reserve for the system (e.g., to not use by
* tmpfs).
- * XXX: Should this be tunable through sysctl, for instance? */
-#define TMPFS_PAGES_RESERVED (4 * 1024 * 1024 / PAGE_SIZE)
+ */
+#define TMPFS_PAGES_MINRESERVED (4 * 1024 * 1024 / PAGE_SIZE)
/*
- * Returns information about the number of available memory pages,
- * including physical and virtual ones.
- *
- * Remember to remove TMPFS_PAGES_RESERVED from the returned value to avoid
- * excessive memory usage.
- *
+ * Number of reserved swap pages should not be lower than
+ * swap_pager_almost_full high water mark.
*/
-static __inline size_t
-tmpfs_mem_info(void)
-{
+#define TMPFS_SWAP_MINRESERVED 1024
- return (swap_pager_avail + cnt.v_free_count + cnt.v_cache_count);
-}
+size_t tmpfs_mem_avail(void);
-/* Returns the maximum size allowed for a tmpfs file system. This macro
- * must be used instead of directly retrieving the value from tm_pages_max.
- * The reason is that the size of a tmpfs file system is dynamic: it lets
- * the user store files as long as there is enough free memory (including
- * physical memory and swap space). Therefore, the amount of memory to be
- * used is either the limit imposed by the user during mount time or the
- * amount of available memory, whichever is lower. To avoid consuming all
- * the memory for a given mount point, the system will always reserve a
- * minimum of TMPFS_PAGES_RESERVED pages, which is also taken into account
- * by this macro (see above). */
static __inline size_t
-TMPFS_PAGES_MAX(struct tmpfs_mount *tmp)
+tmpfs_pages_used(struct tmpfs_mount *tmp)
{
- size_t freepages;
-
- freepages = tmpfs_mem_info();
- freepages -= freepages < TMPFS_PAGES_RESERVED ?
- freepages : TMPFS_PAGES_RESERVED;
+ const size_t node_size = sizeof(struct tmpfs_node) +
+ sizeof(struct tmpfs_dirent);
+ size_t meta_pages;
- return MIN(tmp->tm_pages_max, freepages + tmp->tm_pages_used);
+ meta_pages = howmany((uintmax_t)tmp->tm_nodes_inuse * node_size,
+ PAGE_SIZE);
+ return (meta_pages + tmp->tm_pages_used);
}
-/* Returns the available space for the given file system. */
-#define TMPFS_META_PAGES(tmp) (howmany((tmp)->tm_nodes_inuse * (sizeof(struct tmpfs_node) \
- + sizeof(struct tmpfs_dirent)), PAGE_SIZE))
-#define TMPFS_FILE_PAGES(tmp) ((tmp)->tm_pages_used)
-
-#define TMPFS_PAGES_AVAIL(tmp) (TMPFS_PAGES_MAX(tmp) > \
- TMPFS_META_PAGES(tmp)+TMPFS_FILE_PAGES(tmp)? \
- TMPFS_PAGES_MAX(tmp) - TMPFS_META_PAGES(tmp) \
- - TMPFS_FILE_PAGES(tmp):0)
-
#endif
/* --------------------------------------------------------------------- */
diff --git a/sys/fs/tmpfs/tmpfs_subr.c b/sys/fs/tmpfs/tmpfs_subr.c
index fe596aa..5123fcc 100644
--- a/sys/fs/tmpfs/tmpfs_subr.c
+++ b/sys/fs/tmpfs/tmpfs_subr.c
@@ -59,6 +59,76 @@ __FBSDID("$FreeBSD$");
SYSCTL_NODE(_vfs, OID_AUTO, tmpfs, CTLFLAG_RW, 0, "tmpfs file system");
+static long tmpfs_swap_reserved = TMPFS_SWAP_MINRESERVED * 2;
+
+static long tmpfs_pages_reserved = TMPFS_PAGES_MINRESERVED;
+
+static int
+sysctl_mem_reserved(SYSCTL_HANDLER_ARGS)
+{
+ int error;
+ long pages, bytes, reserved;
+
+ pages = *(long *)arg1;
+ bytes = pages * PAGE_SIZE;
+
+ error = sysctl_handle_long(oidp, &bytes, 0, req);
+ if (error || !req->newptr)
+ return (error);
+
+ pages = bytes / PAGE_SIZE;
+ if (arg1 == &tmpfs_swap_reserved)
+ reserved = TMPFS_SWAP_MINRESERVED;
+ else
+ reserved = TMPFS_PAGES_MINRESERVED;
+ if (pages < reserved)
+ return (EINVAL);
+
+ *(long *)arg1 = pages;
+ return (0);
+}
+
+SYSCTL_PROC(_vfs_tmpfs, OID_AUTO, memory_reserved, CTLTYPE_LONG|CTLFLAG_RW,
+ &tmpfs_pages_reserved, 0, sysctl_mem_reserved, "L", "reserved memory");
+SYSCTL_PROC(_vfs_tmpfs, OID_AUTO, swap_reserved, CTLTYPE_LONG|CTLFLAG_RW,
+ &tmpfs_swap_reserved, 0, sysctl_mem_reserved, "L", "reserved swap memory");
+
+size_t
+tmpfs_mem_avail(void)
+{
+ vm_ooffset_t avail_swap, avail_mem;
+
+ avail_swap = swap_pager_avail - tmpfs_swap_reserved;
+ if (__predict_false(avail_swap <= 0)) {
+ /* FIXME No swap or disabled swap check */
+ if (swap_pager_avail == 0)
+ avail_swap = 0;
+ else
+ return (0);
+ }
+ avail_mem = cnt.v_free_count + cnt.v_cache_count - tmpfs_pages_reserved;
+ if (__predict_false(avail_mem < 0))
+ avail_mem = 0;
+ return (avail_swap + avail_mem);
+}
+
+static size_t
+tmpfs_pages_check_avail(struct tmpfs_mount *tmp, size_t req_pages)
+{
+ size_t avail;
+
+ avail = tmpfs_mem_avail();
+ if (avail < req_pages)
+ return (0);
+
+ if (tmp->tm_pages_max != SIZE_MAX)
+ avail = tmp->tm_pages_max - tmpfs_pages_used(tmp);
+ if (avail < req_pages)
+ return (0);
+
+ return (1);
+}
+
/* --------------------------------------------------------------------- */
/*
@@ -99,6 +169,8 @@ tmpfs_alloc_node(struct tmpfs_mount *tmp, enum vtype type,
if (tmp->tm_nodes_inuse >= tmp->tm_nodes_max)
return (ENOSPC);
+ if (tmpfs_pages_check_avail(tmp, 1) == 0)
+ return (ENOSPC);
nnode = (struct tmpfs_node *)uma_zalloc_arg(
tmp->tm_node_pool, tmp, M_WAITOK);
@@ -917,7 +989,7 @@ tmpfs_reg_resize(struct vnode *vp, off_t newsize, boolean_t ignerr)
MPASS(oldpages == uobj->size);
newpages = OFF_TO_IDX(newsize + PAGE_MASK);
if (newpages > oldpages &&
- newpages - oldpages > TMPFS_PAGES_AVAIL(tmp))
+ tmpfs_pages_check_avail(tmp, newpages - oldpages) == 0)
return (ENOSPC);
VM_OBJECT_LOCK(uobj);
diff --git a/sys/fs/tmpfs/tmpfs_vfsops.c b/sys/fs/tmpfs/tmpfs_vfsops.c
index 0647ba2..2ad7eb4 100644
--- a/sys/fs/tmpfs/tmpfs_vfsops.c
+++ b/sys/fs/tmpfs/tmpfs_vfsops.c
@@ -129,17 +129,62 @@ tmpfs_node_fini(void *mem, int size)
mtx_destroy(&node->tn_interlock);
}
+/*
+ * XXX Rename to vfs_getopt_size()
+ */
+static int
+tmpfs_getopt_size(struct vfsoptlist *opts, const char *name, u_quad_t *data)
+{
+ char *opt_value, *vtp;
+ quad_t iv;
+ int error, opt_len;
+
+ error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len);
+ if (error != 0)
+ return (error);
+ if (opt_len == 0 || opt_value == NULL)
+ return (EINVAL);
+ if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0')
+ return (EINVAL);
+
+ iv = strtoq(opt_value, &vtp, 0);
+ if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0'))
+ return (EINVAL);
+ if (iv < 0)
+ return (EINVAL);
+ switch (vtp[0]) {
+ case 't':
+ case 'T':
+ iv *= 1024;
+ case 'g':
+ case 'G':
+ iv *= 1024;
+ case 'm':
+ case 'M':
+ iv *= 1024;
+ case 'k':
+ case 'K':
+ iv *= 1024;
+ case '\0':
+ break;
+ default:
+ return (EINVAL);
+ }
+ *data = iv;
+
+ return (0);
+}
+
static int
tmpfs_mount(struct mount *mp)
{
+ const size_t nodes_per_page = howmany(PAGE_SIZE,
+ sizeof(struct tmpfs_dirent) + sizeof(struct tmpfs_node));
struct tmpfs_mount *tmp;
struct tmpfs_node *root;
- size_t pages;
- uint32_t nodes;
int error;
/* Size counters. */
- u_int nodes_max;
- u_quad_t size_max, maxfilesize;
+ u_quad_t pages, nodes_max, size_max, maxfilesize;
/* Root node attributes. */
uid_t root_uid;
@@ -175,46 +220,47 @@ tmpfs_mount(struct mount *mp)
if (mp->mnt_cred->cr_ruid != 0 ||
vfs_scanopt(mp->mnt_optnew, "mode", "%ho", &root_mode) != 1)
root_mode = va.va_mode;
- if (vfs_scanopt(mp->mnt_optnew, "inodes", "%u", &nodes_max) != 1)
+ if (tmpfs_getopt_size(mp->mnt_optnew, "inodes", &nodes_max) != 0)
nodes_max = 0;
- if (vfs_scanopt(mp->mnt_optnew, "size", "%qu", &size_max) != 1)
+ if (tmpfs_getopt_size(mp->mnt_optnew, "size", &size_max) != 0)
size_max = 0;
- if (vfs_scanopt(mp->mnt_optnew, "maxfilesize", "%qu",
- &maxfilesize) != 1)
+ if (tmpfs_getopt_size(mp->mnt_optnew, "maxfilesize", &maxfilesize) != 0)
maxfilesize = 0;
/* Do not allow mounts if we do not have enough memory to preserve
* the minimum reserved pages. */
- if (tmpfs_mem_info() < TMPFS_PAGES_RESERVED)
+ if (tmpfs_mem_avail() < TMPFS_PAGES_MINRESERVED)
return ENOSPC;
/* Get the maximum number of memory pages this file system is
* allowed to use, based on the maximum size the user passed in
* the mount structure. A value of zero is treated as if the
* maximum available space was requested. */
- if (size_max < PAGE_SIZE || size_max > SIZE_MAX - PAGE_SIZE)
+ if (size_max < PAGE_SIZE || size_max > OFF_MAX - PAGE_SIZE ||
+ (SIZE_MAX < OFF_MAX && size_max / PAGE_SIZE >= SIZE_MAX))
pages = SIZE_MAX;
else
pages = howmany(size_max, PAGE_SIZE);
MPASS(pages > 0);
if (nodes_max <= 3) {
- if (pages > UINT32_MAX - 3)
- nodes = UINT32_MAX;
+ if (pages < INT_MAX / nodes_per_page)
+ nodes_max = pages * nodes_per_page;
else
- nodes = pages + 3;
- } else
- nodes = nodes_max;
- MPASS(nodes >= 3);
+ nodes_max = INT_MAX;
+ }
+ if (nodes_max > INT_MAX)
+ nodes_max = INT_MAX;
+ MPASS(nodes_max >= 3);
/* Allocate the tmpfs mount structure and fill it. */
tmp = (struct tmpfs_mount *)malloc(sizeof(struct tmpfs_mount),
M_TMPFSMNT, M_WAITOK | M_ZERO);
mtx_init(&tmp->allnode_lock, "tmpfs allnode lock", NULL, MTX_DEF);
- tmp->tm_nodes_max = nodes;
+ tmp->tm_nodes_max = nodes_max;
tmp->tm_nodes_inuse = 0;
- tmp->tm_maxfilesize = maxfilesize > 0 ? maxfilesize : UINT64_MAX;
+ tmp->tm_maxfilesize = maxfilesize > 0 ? maxfilesize : OFF_MAX;
LIST_INIT(&tmp->tm_nodes_used);
tmp->tm_pages_max = pages;
@@ -384,22 +430,26 @@ tmpfs_fhtovp(struct mount *mp, struct fid *fhp, int flags,
static int
tmpfs_statfs(struct mount *mp, struct statfs *sbp)
{
- fsfilcnt_t freenodes;
struct tmpfs_mount *tmp;
+ size_t used;
tmp = VFS_TO_TMPFS(mp);
sbp->f_iosize = PAGE_SIZE;
sbp->f_bsize = PAGE_SIZE;
- sbp->f_blocks = TMPFS_PAGES_MAX(tmp);
- sbp->f_bavail = sbp->f_bfree = TMPFS_PAGES_AVAIL(tmp);
-
- freenodes = MIN(tmp->tm_nodes_max - tmp->tm_nodes_inuse,
- TMPFS_PAGES_AVAIL(tmp) * PAGE_SIZE / sizeof(struct tmpfs_node));
-
- sbp->f_files = freenodes + tmp->tm_nodes_inuse;
- sbp->f_ffree = freenodes;
+ used = tmpfs_pages_used(tmp);
+ if (tmp->tm_pages_max != SIZE_MAX)
+ sbp->f_blocks = tmp->tm_pages_max;
+ else
+ sbp->f_blocks = used + tmpfs_mem_avail();
+ if (sbp->f_blocks <= used)
+ sbp->f_bavail = 0;
+ else
+ sbp->f_bavail = sbp->f_blocks - used;
+ sbp->f_bfree = sbp->f_bavail;
+ sbp->f_files = tmp->tm_nodes_max;
+ sbp->f_ffree = tmp->tm_nodes_max - tmp->tm_nodes_inuse;
/* sbp->f_owner = tmp->tn_uid; */
return 0;
More information about the freebsd-current
mailing list