diff options
| -rw-r--r-- | ChangeLog | 1 | ||||
| -rw-r--r-- | cloudinit/config/cc_mounts.py | 157 | ||||
| -rw-r--r-- | cloudinit/util.py | 50 | ||||
| -rw-r--r-- | doc/examples/cloud-config-mount-points.txt | 7 |
4 files changed, 215 insertions, 0 deletions
@@ -38,6 +38,7 @@ - cc_grub_dpkg: fix EC2 hvm instances to avoid prompt on grub update. (LP: #1336855) - FreeBsd: support config drive datasource [Joseph bajin] + - cc_mounts: support creating a swap file 0.7.5: - open 0.7.5 - Add a debug log message around import failures diff --git a/cloudinit/config/cc_mounts.py b/cloudinit/config/cc_mounts.py index ba1303d1..1cb1e839 100644 --- a/cloudinit/config/cc_mounts.py +++ b/cloudinit/config/cc_mounts.py @@ -75,6 +75,159 @@ def sanitize_devname(startname, transformer, log): return devnode_for_dev_part(blockdev, part) +def suggested_swapsize(memsize=None, maxsize=None, fsys=None): + # make a suggestion on the size of swap for this system. + if memsize is None: + memsize = util.read_meminfo()['total'] + + GB = 2 ** 30 + sugg_max = 8 * GB + + info = {'avail': 'na', 'max_in': maxsize, 'mem': memsize} + + if fsys is None and maxsize is None: + # set max to 8GB default if no filesystem given + maxsize = sugg_max + elif fsys: + statvfs = os.statvfs(fsys) + avail = statvfs.f_frsize * statvfs.f_bfree + info['avail'] = avail + + if maxsize is None: + # set to 25% of filesystem space + maxsize = min(int(avail / 4), sugg_max) + elif maxsize > ((avail * .9)): + # set to 90% of available disk space + maxsize = int(avail * .9) + elif maxsize is None: + maxsize = sugg_max + + info['max'] = maxsize + + formulas = [ + # < 1G: swap = double memory + (1 * GB, lambda x: x * 2), + # < 2G: swap = 2G + (2 * GB, lambda x: 2 * GB), + # < 4G: swap = memory + (4 * GB, lambda x: x), + # < 16G: 4G + (16 * GB, lambda x: 4 * GB), + # < 64G: 1/2 M up to max + (64 * GB, lambda x: x / 2), + ] + + size = None + for top, func in formulas: + if memsize <= top: + size = min(func(memsize), maxsize) + # if less than 1/2 memory and not much, return 0 + if size < (memsize / 2) and size < 4 * GB: + size = 0 + break + break + + if size is not None: + size = maxsize + + info['size'] = size + + MB = 2 ** 20 + pinfo = {} + for k, v in info.items(): + if isinstance(v, int): + pinfo[k] = "%s MB" % (v / MB) + else: + pinfo[k] = v + + LOG.debug("suggest %(size)s swap for %(mem)s memory with '%(avail)s'" + " disk given max=%(max_in)s [max=%(max)s]'" % pinfo) + return size + + +def setup_swapfile(fname, size=None, maxsize=None): + """ + fname: full path string of filename to setup + size: the size to create. set to "auto" for recommended + maxsize: the maximum size + """ + tdir = os.path.dirname(fname) + if str(size).lower() == "auto": + try: + memsize = util.read_meminfo()['total'] + except IOError as e: + LOG.debug("Not creating swap. failed to read meminfo") + return + + util.ensure_dir(tdir) + size = suggested_swapsize(fsys=tdir, maxsize=maxsize, + memsize=memsize) + + if not size: + LOG.debug("Not creating swap: suggested size was 0") + return + + mbsize = str(int(size / (2 ** 20))) + msg = "creating swap file '%s' of %sMB" % (fname, mbsize) + try: + util.ensure_dir(tdir) + util.log_time(LOG.debug, msg, func=util.subp, + args=[['sh', '-c', + ('rm -f "$1" && umask 0066 && ' + 'dd if=/dev/zero "of=$1" bs=1M "count=$2" && ' + 'mkswap "$1" || { r=$?; rm -f "$1"; exit $r; }'), + 'setup_swap', fname, mbsize]]) + + except Exception as e: + raise IOError("Failed %s: %s" % (msg, e)) + + return fname + + +def handle_swapcfg(swapcfg): + """handle the swap config, calling setup_swap if necessary. + return None or (filename, size) + """ + if not isinstance(swapcfg, dict): + LOG.warn("input for swap config was not a dict.") + return None + + fname = swapcfg.get('filename', '/swap.img') + size = swapcfg.get('size', 0) + maxsize = swapcfg.get('maxsize', None) + + if not (size and fname): + LOG.debug("no need to setup swap") + return + + if os.path.exists(fname): + if not os.path.exists("/proc/swaps"): + LOG.debug("swap file %s existed. no /proc/swaps. Being safe.", + fname) + return fname + try: + for line in util.load_file("/proc/swaps").splitlines(): + if line.startswith(fname + " "): + LOG.debug("swap file %s already in use.", fname) + return fname + LOG.debug("swap file %s existed, but not in /proc/swaps", fname) + except: + LOG.warn("swap file %s existed. Error reading /proc/swaps", fname) + return fname + + try: + if isinstance(size, str) and size != "auto": + size = util.human2bytes(size) + if isinstance(maxsize, str): + maxsize = util.human2bytes(maxsize) + return setup_swapfile(fname=fname, size=size, maxsize=maxsize) + + except Exception as e: + LOG.warn("failed to setup swap: %s", e) + + return None + + def handle(_name, cfg, cloud, log, _args): # fs_spec, fs_file, fs_vfstype, fs_mntops, fs-freq, fs_passno defvals = [None, None, "auto", "defaults,nobootwait", "0", "2"] @@ -162,6 +315,10 @@ def handle(_name, cfg, cloud, log, _args): else: actlist.append(x) + swapret = handle_swapcfg(cfg.get('swap', {})) + if swapret: + actlist.append([swapret, "none", "swap", "sw", "0", "0"]) + if len(actlist) == 0: log.debug("No modifications to fstab needed.") return diff --git a/cloudinit/util.py b/cloudinit/util.py index 76e91951..f236d0bf 100644 --- a/cloudinit/util.py +++ b/cloudinit/util.py @@ -1957,3 +1957,53 @@ def pathprefix2dict(base, required=None, optional=None, delim=os.path.sep): raise ValueError("Missing required files: %s", ','.join(missing)) return ret + + +def read_meminfo(meminfo="/proc/meminfo", raw=False): + # read a /proc/meminfo style file and return + # a dict with 'total', 'free', and 'available' + mpliers = {'kB': 2**10, 'mB': 2 ** 20, 'B': 1, 'gB': 2 ** 30} + kmap = {'MemTotal:': 'total', 'MemFree:': 'free', + 'MemAvailable:': 'available'} + ret = {} + for line in load_file(meminfo).splitlines(): + try: + key, value, unit = line.split() + except ValueError: + key, value = line.split() + unit = 'B' + if raw: + ret[key] = int(value) * mpliers[unit] + elif key in kmap: + ret[kmap[key]] = int(value) * mpliers[unit] + + return ret + + +def human2bytes(size): + """Convert human string or integer to size in bytes + 10M => 10485760 + .5G => 536870912 + """ + size_in = size + if size.endswith("B"): + size = size[:-1] + + mpliers = {'B': 1, 'K': 2 ** 10, 'M': 2 ** 20, 'G': 2 ** 30, 'T': 2 ** 40} + + num = size + mplier = 'B' + for m in mpliers: + if size.endswith(m): + mplier = m + num = size[0:-len(m)] + + try: + num = float(num) + except ValueError: + raise ValueError("'%s' is not valid input." % size_in) + + if num < 0: + raise ValueError("'%s': cannot be negative" % size_in) + + return int(num * mpliers[mplier]) diff --git a/doc/examples/cloud-config-mount-points.txt b/doc/examples/cloud-config-mount-points.txt index 416006db..3b45b47f 100644 --- a/doc/examples/cloud-config-mount-points.txt +++ b/doc/examples/cloud-config-mount-points.txt @@ -37,3 +37,10 @@ mounts: # complete. This must be an array, and must have 7 fields. mount_default_fields: [ None, None, "auto", "defaults,nobootwait", "0", "2" ] + +# swap can also be set up by the 'mounts' module +# default is to not create any swap files, because 'size' is set to 0 +swap: + filename: /swap.img + size: "auto" or size in bytes + maxsize: size in bytes |