What does persistent_id means,
it could reuse/share the same existed connection in one foo.php script?
I have read following documentations couple of times, it doesn't help.
http://www.php.net/manual/en/class.memcached.php
https://github.com/php-memcached-dev/php-memcached/blob/master/tests/construct_persistent.phpt
I do some tests, everything I do is making me more confused.
Test envorinment:
- memcached-1.4.15
- php-5.4.10
- libmemcached-1.0.11
- Ubuntu 12.04 64bit
TCP conn state watch script
cat watch_tw.sh
#!/usr/bin/env bash
while true; do
ss -s | grep ^TCP:
sleep 1
done
Start memcached
memcached -v -c 4096 -m 64 -p 11211 -u www-data
Tset I
ab -c 100 -n 1000 http://t.m.com/index-without-pool.php
ab reports
Percentage of the requests served within a certain time (ms)
50% 38
66% 41
75% 42
80% 43
90% 45
95% 46
98% 52
99% 56
100% 59 (longest request)
ss reports
TCP: 2024 (estab 3, closed 2001, orphaned 0, synrecv 0, timewait 2001/0), ports 0
after 40 seconds, ss reports
TCP: 23 (estab 3, closed 0, orphaned 0, synrecv 0, timewait 0/0), ports 0
It is as expected.
Test II
ab -c 100 -n 1000 http://t.m.com/index-pool.php
ab reports
Percentage of the requests served within a certain time (ms)
50% 558
66% 607
75% 626
80% 636
90% 664
95% 690
98% 723
99% 744
100% 772 (longest request)
ss reports
TCP: 2247 (estab 451, closed 1776, orphaned 0, synrecv 0, timewait 1776/0), ports 0
after 40 seconds, ss reports
TCP: 471 (estab 451, closed 0, orphaned 0, synrecv 0, timewait 0/0), ports 0
Questions
- Why it is slowly?
- Why memcached keep connection after php-fpm process has terminated?
Environment settings
index-without-pool.php
<?php
$mc = new Memcached();
$mc->addServer("127.0.0.1", 11211);
$mc->setOption(Memcached::OPT_CONNECT_TIMEOUT, 5);
$mc->set("a", "b");
$val = $mc->get("a");
if (!$val) {
echo "get val failed";
}
$stats = $mc->getStats();
$curr_conns = $stats["127.0.0.1:11211"]["curr_connections"];
echo $curr_conns;
echo "\n";
index-pool.php
<?php
$mc = new Memcached("pool_test");
if (empty($sl)) {
$mc->addServer("127.0.0.1", 11211);
$mc->setOption(Memcached::OPT_CONNECT_TIMEOUT, 5);
}
$mc->set("a", "b");
$val = $mc->get("a");
if (!$val) {
echo "get val failed";
}
$stats = $mc->getStats();
$curr_conns = $stats["127.0.0.1:11211"]["curr_connections"];
echo $curr_conns;
echo "\n";
php.ini
[PHP]
engine = On
short_open_tag = Off
asp_tags = Off
precision = 14
output_buffering = 4096
zlib.output_compression = Off
implicit_flush = Off
unserialize_callback_func =
serialize_precision = 17
disable_functions =
disable_classes =
zend.enable_gc = On
expose_php = On
max_execution_time = 10
max_input_time = 60
memory_limit = 128M
error_reporting = E_ALL
display_errors = On
display_startup_errors = On
log_errors = On
log_errors_max_len = 1024
ignore_repeated_errors = Off
ignore_repeated_source = Off
report_memleaks = On
track_errors = On
html_errors = On
error_log = /usr/local/php/var/log/error.log
variables_order = "GPCS"
request_order = "GP"
register_argc_argv = Off
auto_globals_jit = On
post_max_size = 8M
auto_prepend_file =
auto_append_file =
default_mimetype = "text/html"
doc_root =
user_dir =
enable_dl = Off
file_uploads = On
upload_max_filesize = 2M
max_file_uploads = 20
allow_url_fopen = On
allow_url_include = Off
default_socket_timeout = 60
[CLI Server]
cli_server.color = On
[Date]
date.timezone="UTC"
[filter]
[iconv]
[intl]
[sqlite]
[sqlite3]
[Pcre]
[Pdo]
[Pdo_mysql]
pdo_mysql.cache_size = 2000
pdo_mysql.default_socket=
[Phar]
[mail function]
SMTP = localhost
smtp_port = 25
mail.add_x_header = On
[SQL]
sql.safe_mode = Off
[ODBC]
odbc.allow_persistent = On
odbc.check_persistent = On
odbc.max_persistent = -1
odbc.max_links = -1
odbc.defaultlrl = 4096
odbc.defaultbinmode = 1
[Interbase]
ibase.allow_persistent = 1
ibase.max_persistent = -1
ibase.max_links = -1
ibase.timestampformat = "%Y-%m-%d %H:%M:%S"
ibase.dateformat = "%Y-%m-%d"
ibase.timeformat = "%H:%M:%S"
[MySQL]
mysql.allow_local_infile = On
mysql.allow_persistent = On
mysql.cache_size = 2000
mysql.max_persistent = -1
mysql.max_links = -1
mysql.default_port =
mysql.default_socket =
mysql.default_host =
mysql.default_user =
mysql.default_password =
mysql.connect_timeout = 60
mysql.trace_mode = Off
[MySQLi]
mysqli.max_persistent = -1
mysqli.allow_persistent = On
mysqli.max_links = -1
mysqli.cache_size = 2000
mysqli.default_port = 3306
mysqli.default_socket =
mysqli.default_host =
mysqli.default_user =
mysqli.default_pw =
mysqli.reconnect = Off
[mysqlnd]
mysqlnd.collect_statistics = On
mysqlnd.collect_memory_statistics = On
[OCI8]
[PostgreSQL]
pgsql.allow_persistent = On
pgsql.auto_reset_persistent = Off
pgsql.max_persistent = -1
pgsql.max_links = -1
pgsql.ignore_notice = 0
pgsql.log_notice = 0
[Sybase-CT]
sybct.allow_persistent = On
sybct.max_persistent = -1
sybct.max_links = -1
sybct.min_server_severity = 10
sybct.min_client_severity = 10
[bcmath]
bcmath.scale = 0
[browscap]
[Session]
session.save_handler = files
session.use_cookies = 1
session.use_only_cookies = 1
session.name = PHPSESSID
session.auto_start = 0
session.cookie_lifetime = 0
session.cookie_path = /
session.cookie_domain =
session.cookie_httponly =
session.serialize_handler = php
session.gc_probability = 1
session.gc_divisor = 1000
session.gc_maxlifetime = 1440
session.bug_compat_42 = On
session.bug_compat_warn = On
session.referer_check =
session.cache_limiter = nocache
session.cache_expire = 180
session.use_trans_sid = 0
session.hash_function = 0
session.hash_bits_per_character = 5
url_rewriter.tags = "a=href,area=href,frame=src,input=src,form=fakeentry"
[MSSQL]
mssql.allow_persistent = On
mssql.max_persistent = -1
mssql.max_links = -1
mssql.min_error_severity = 10
mssql.min_message_severity = 10
mssql.compatability_mode = Off
mssql.secure_connection = Off
[Assertion]
[COM]
[mbstring]
[gd]
[exif]
[Tidy]
tidy.clean_output = Off
[soap]
soap.wsdl_cache_enabled=1
soap.wsdl_cache_dir="/tmp"
soap.wsdl_cache_ttl=86400
soap.wsdl_cache_limit = 5
[sysvshm]
[ldap]
ldap.max_links = -1
[mcrypt]
[dba]
[xhprof]
extension=xhprof.so
xhprof.output_dir=/tmp/xhprof
[memcached]
extension=memcached.so
php-fpm.conf
[global]
pid = /usr/local/php/var/run/php-fpm.pid
error_log = /usr/local/php/var/log/php-fpm.log
log_level = warning
rlimit_files = 10240
rlimit_core = 0
[www]
user = www-data
group = www-data
listen = /dev/shm/php-fpm.sock
pm = dynamic
pm.max_children = 512
pm.start_servers = 2
pm.min_spare_servers = 1
pm.max_spare_servers = 3
pm.status_path = /status
ping.path = /ping
ping.response = pong
slowlog = /usr/local/php/var/log/$pool.log.slow
request_slowlog_timeout = 3
request_terminate_timeout = 10
chdir = /var/www
sysctl -a
net.ipv4.route.gc_thresh = 131072
net.ipv4.route.max_size = 2097152
net.ipv4.route.gc_min_interval = 0
net.ipv4.route.gc_min_interval_ms = 500
net.ipv4.route.gc_timeout = 300
net.ipv4.route.gc_interval = 60
net.ipv4.route.redirect_load = 5
net.ipv4.route.redirect_number = 9
net.ipv4.route.redirect_silence = 5120
net.ipv4.route.gc_elasticity = 8
net.ipv4.route.mtu_expires = 600
net.ipv4.route.min_pmtu = 552
net.ipv4.route.min_adv_mss = 256
net.ipv4.neigh.default.mcast_solicit = 3
net.ipv4.neigh.default.ucast_solicit = 3
net.ipv4.neigh.default.app_solicit = 0
net.ipv4.neigh.default.retrans_time = 100
net.ipv4.neigh.default.base_reachable_time = 30
net.ipv4.neigh.default.delay_first_probe_time = 5
net.ipv4.neigh.default.gc_stale_time = 60
net.ipv4.neigh.default.unres_qlen = 3
net.ipv4.neigh.default.proxy_qlen = 64
net.ipv4.neigh.default.anycast_delay = 100
net.ipv4.neigh.default.proxy_delay = 80
net.ipv4.neigh.default.locktime = 100
net.ipv4.neigh.default.retrans_time_ms = 1000
net.ipv4.neigh.default.base_reachable_time_ms = 30000
net.ipv4.neigh.default.gc_interval = 30
net.ipv4.neigh.default.gc_thresh1 = 128
net.ipv4.neigh.default.gc_thresh2 = 512
net.ipv4.neigh.default.gc_thresh3 = 1024
net.ipv4.neigh.lo.mcast_solicit = 3
net.ipv4.neigh.lo.ucast_solicit = 3
net.ipv4.neigh.lo.app_solicit = 0
net.ipv4.neigh.lo.retrans_time = 100
net.ipv4.neigh.lo.base_reachable_time = 30
net.ipv4.neigh.lo.delay_first_probe_time = 5
net.ipv4.neigh.lo.gc_stale_time = 60
net.ipv4.neigh.lo.unres_qlen = 3
net.ipv4.neigh.lo.proxy_qlen = 64
net.ipv4.neigh.lo.anycast_delay = 100
net.ipv4.neigh.lo.proxy_delay = 80
net.ipv4.neigh.lo.locktime = 100
net.ipv4.neigh.lo.retrans_time_ms = 1000
net.ipv4.neigh.lo.base_reachable_time_ms = 30000
net.ipv4.neigh.eth0.mcast_solicit = 3
net.ipv4.neigh.eth0.ucast_solicit = 3
net.ipv4.neigh.eth0.app_solicit = 0
net.ipv4.neigh.eth0.retrans_time = 100
net.ipv4.neigh.eth0.base_reachable_time = 30
net.ipv4.neigh.eth0.delay_first_probe_time = 5
net.ipv4.neigh.eth0.gc_stale_time = 60
net.ipv4.neigh.eth0.unres_qlen = 3
net.ipv4.neigh.eth0.proxy_qlen = 64
net.ipv4.neigh.eth0.anycast_delay = 100
net.ipv4.neigh.eth0.proxy_delay = 80
net.ipv4.neigh.eth0.locktime = 100
net.ipv4.neigh.eth0.retrans_time_ms = 1000
net.ipv4.neigh.eth0.base_reachable_time_ms = 30000
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_sack = 1
net.ipv4.tcp_retrans_collapse = 1
net.ipv4.ip_default_ttl = 64
net.ipv4.ip_no_pmtu_disc = 0
net.ipv4.ip_nonlocal_bind = 0
net.ipv4.tcp_syn_retries = 5
net.ipv4.tcp_synack_retries = 5
net.ipv4.tcp_max_orphans = 262144
net.ipv4.tcp_max_tw_buckets = 262144
net.ipv4.ip_dynaddr = 0
net.ipv4.tcp_keepalive_time = 7200
net.ipv4.tcp_keepalive_probes = 9
net.ipv4.tcp_keepalive_intvl = 75
net.ipv4.tcp_retries1 = 3
net.ipv4.tcp_retries2 = 15
net.ipv4.tcp_fin_timeout = 60
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_tw_recycle = 0
net.ipv4.tcp_abort_on_overflow = 0
net.ipv4.tcp_stdurg = 0
net.ipv4.tcp_rfc1337 = 0
net.ipv4.tcp_max_syn_backlog = 2048
net.ipv4.ip_local_port_range = 32768 61000
net.ipv4.ip_local_reserved_ports =
net.ipv4.igmp_max_memberships = 20
net.ipv4.igmp_max_msf = 10
net.ipv4.inet_peer_threshold = 65664
net.ipv4.inet_peer_minttl = 120
net.ipv4.inet_peer_maxttl = 600
net.ipv4.tcp_orphan_retries = 0
net.ipv4.tcp_fack = 1
net.ipv4.tcp_reordering = 3
net.ipv4.tcp_ecn = 2
net.ipv4.tcp_dsack = 1
net.ipv4.tcp_mem = 90411 120551 180822
net.ipv4.tcp_wmem = 4096 16384 3857632
net.ipv4.tcp_rmem = 4096 87380 3857632
net.ipv4.tcp_app_win = 31
net.ipv4.tcp_adv_win_scale = 1
net.ipv4.tcp_tw_reuse = 0
net.ipv4.tcp_frto = 2
net.ipv4.tcp_frto_response = 0
net.ipv4.tcp_low_latency = 0
net.ipv4.tcp_no_metrics_save = 0
net.ipv4.tcp_moderate_rcvbuf = 1
net.ipv4.tcp_tso_win_divisor = 3
net.ipv4.tcp_congestion_control = cubic
net.ipv4.tcp_abc = 0
net.ipv4.tcp_mtu_probing = 0
net.ipv4.tcp_base_mss = 512
net.ipv4.tcp_workaround_signed_windows = 0
net.ipv4.tcp_dma_copybreak = 4096
net.ipv4.tcp_slow_start_after_idle = 1
net.ipv4.cipso_cache_enable = 1
net.ipv4.cipso_cache_bucket_size = 10
net.ipv4.cipso_rbm_optfmt = 0
net.ipv4.cipso_rbm_strictvalid = 1
net.ipv4.tcp_available_congestion_control = cubic reno
net.ipv4.tcp_allowed_congestion_control = cubic reno
net.ipv4.tcp_max_ssthresh = 0
net.ipv4.tcp_cookie_size = 0
net.ipv4.tcp_thin_linear_timeouts = 0
net.ipv4.tcp_thin_dupack = 0
net.ipv4.udp_mem = 90411 120551 180822
net.ipv4.udp_rmem_min = 4096
net.ipv4.udp_wmem_min = 4096
net.ipv4.conf.all.forwarding = 0
net.ipv4.conf.all.mc_forwarding = 0
net.ipv4.conf.all.accept_redirects = 1
net.ipv4.conf.all.secure_redirects = 1
net.ipv4.conf.all.shared_media = 1
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.all.send_redirects = 1
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.all.accept_local = 0
net.ipv4.conf.all.src_valid_mark = 0
net.ipv4.conf.all.proxy_arp = 0
net.ipv4.conf.all.medium_id = 0
net.ipv4.conf.all.bootp_relay = 0
net.ipv4.conf.all.log_martians = 0
net.ipv4.conf.all.tag = 0
net.ipv4.conf.all.arp_filter = 0
net.ipv4.conf.all.arp_announce = 0
net.ipv4.conf.all.arp_ignore = 0
net.ipv4.conf.all.arp_accept = 0
net.ipv4.conf.all.arp_notify = 0
net.ipv4.conf.all.proxy_arp_pvlan = 0
net.ipv4.conf.all.disable_xfrm = 0
net.ipv4.conf.all.disable_policy = 0
net.ipv4.conf.all.force_igmp_version = 0
net.ipv4.conf.all.promote_secondaries = 0
net.ipv4.conf.default.forwarding = 0
net.ipv4.conf.default.mc_forwarding = 0
net.ipv4.conf.default.accept_redirects = 1
net.ipv4.conf.default.secure_redirects = 1
net.ipv4.conf.default.shared_media = 1
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.send_redirects = 1
net.ipv4.conf.default.accept_source_route = 1
net.ipv4.conf.default.accept_local = 0
net.ipv4.conf.default.src_valid_mark = 0
net.ipv4.conf.default.proxy_arp = 0
net.ipv4.conf.default.medium_id = 0
net.ipv4.conf.default.bootp_relay = 0
net.ipv4.conf.default.log_martians = 0
net.ipv4.conf.default.tag = 0
net.ipv4.conf.default.arp_filter = 0
net.ipv4.conf.default.arp_announce = 0
net.ipv4.conf.default.arp_ignore = 0
net.ipv4.conf.default.arp_accept = 0
net.ipv4.conf.default.arp_notify = 0
net.ipv4.conf.default.proxy_arp_pvlan = 0
net.ipv4.conf.default.disable_xfrm = 0
net.ipv4.conf.default.disable_policy = 0
net.ipv4.conf.default.force_igmp_version = 0
net.ipv4.conf.default.promote_secondaries = 0
net.ipv4.conf.lo.forwarding = 0
net.ipv4.conf.lo.mc_forwarding = 0
net.ipv4.conf.lo.accept_redirects = 1
net.ipv4.conf.lo.secure_redirects = 1
net.ipv4.conf.lo.shared_media = 1
net.ipv4.conf.lo.rp_filter = 1
net.ipv4.conf.lo.send_redirects = 1
net.ipv4.conf.lo.accept_source_route = 1
net.ipv4.conf.lo.accept_local = 0
net.ipv4.conf.lo.src_valid_mark = 0
net.ipv4.conf.lo.proxy_arp = 0
net.ipv4.conf.lo.medium_id = 0
net.ipv4.conf.lo.bootp_relay = 0
net.ipv4.conf.lo.log_martians = 0
net.ipv4.conf.lo.tag = 0
net.ipv4.conf.lo.arp_filter = 0
net.ipv4.conf.lo.arp_announce = 0
net.ipv4.conf.lo.arp_ignore = 0
net.ipv4.conf.lo.arp_accept = 0
net.ipv4.conf.lo.arp_notify = 0
net.ipv4.conf.lo.proxy_arp_pvlan = 0
net.ipv4.conf.lo.disable_xfrm = 1
net.ipv4.conf.lo.disable_policy = 1
net.ipv4.conf.lo.force_igmp_version = 0
net.ipv4.conf.lo.promote_secondaries = 0
net.ipv4.conf.eth0.forwarding = 0
net.ipv4.conf.eth0.mc_forwarding = 0
net.ipv4.conf.eth0.accept_redirects = 1
net.ipv4.conf.eth0.secure_redirects = 1
net.ipv4.conf.eth0.shared_media = 1
net.ipv4.conf.eth0.rp_filter = 1
net.ipv4.conf.eth0.send_redirects = 1
net.ipv4.conf.eth0.accept_source_route = 1
net.ipv4.conf.eth0.accept_local = 0
net.ipv4.conf.eth0.src_valid_mark = 0
net.ipv4.conf.eth0.proxy_arp = 0
net.ipv4.conf.eth0.medium_id = 0
net.ipv4.conf.eth0.bootp_relay = 0
net.ipv4.conf.eth0.log_martians = 0
net.ipv4.conf.eth0.tag = 0
net.ipv4.conf.eth0.arp_filter = 0
net.ipv4.conf.eth0.arp_announce = 0
net.ipv4.conf.eth0.arp_ignore = 0
net.ipv4.conf.eth0.arp_accept = 0
net.ipv4.conf.eth0.arp_notify = 0
net.ipv4.conf.eth0.proxy_arp_pvlan = 0
net.ipv4.conf.eth0.disable_xfrm = 0
net.ipv4.conf.eth0.disable_policy = 0
net.ipv4.conf.eth0.force_igmp_version = 0
net.ipv4.conf.eth0.promote_secondaries = 0
net.ipv4.ip_forward = 0
net.ipv4.xfrm4_gc_thresh = 1048576
net.ipv4.ipfrag_high_thresh = 262144
net.ipv4.ipfrag_low_thresh = 196608
net.ipv4.ipfrag_time = 30
net.ipv4.icmp_echo_ignore_all = 0
net.ipv4.icmp_echo_ignore_broadcasts = 1
net.ipv4.icmp_ratelimit = 1000
net.ipv4.icmp_ratemask = 6168
net.ipv4.rt_cache_rebuild_count = 4
net.ipv4.ping_group_range = 1 0
net.ipv4.ipfrag_secret_interval = 600
net.ipv4.ipfrag_max_dist = 64