[mysqldumpslow 出错] Died at /usr/local/mysql/bin/mysqldumps
[mysqldumpslow 报错] Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. mysqldumpslow报错: Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. 总结:是因为top数目太多了,mysqldumpslow遍历不过来的缘故。 /usr/local/m
[mysqldumpslow 报错] Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236.mysqldumpslow报错:Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236.
总结:是因为top数目太多了,mysqldumpslow遍历不过来的缘故。
/usr/local/mysql/bin/mysqldumpslow -s -t 15 /root/db01-102-slow.log
1,把r去掉试试,还是报错,参数不识别。
[root@slave ]# /usr/local/mysql/bin/mysqldumpslow -s -t 15 /root/db01-102-slow.log Reading mysql slow query log from 15 /root/db01-102-slow.log Can't open 15: 没有那个文件或目录 at /usr/local/mysql/bin/mysqldumpslow line 91. Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [dubbo]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [dubbo]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [dubbo]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [dubbo]@[xx] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [dubbo]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S')
2,查看下mysqldumpslow 使用参数,-s后面需要带参数的,看了西夏at比较合适
[root@db-master-2 ~]# /usr/local/mysql/bin/mysqldumpslow --help Usage: mysqldumpslow [ OPTS... ] [ LOGS... ] Parse and summarize the MySQL slow query log. Options are --verbose verbose --debug debug --help write this text to standard output -v verbose -d debug -s ORDER what to sort by (al, at, ar, c, l, r, t), 'at' is default al: average lock time ar: average rows sent at: average query time c: count l: lock time r: rows sent t: query time -r reverse the sort order (largest last instead of first) -t NUM just show the top n queries -a don't abstract all numbers to N and strings to 'S' -n NUM abstract numbers with at least n digits within names -g PATTERN grep: only consider stmts that include this string -h HOSTNAME hostname of db server for *-slow.log filename (can be wildcard), default is '*', i.e. match all -i NAME name of server instance (if using mysql.server startup script) -l don't subtract lock time from total time
[root@db-master-2 ~]# /usr/local/mysql/bin/mysqldumpslow -s at -t 15 /root/db01-102-slow.log Reading mysql slow query log from /root/db01-102-slow.log Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [dubbo]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [dubbo]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S') Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [dubbo]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [dubbo]@[10.10.3.8] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [dubbo]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236.
4,去看看/usr/local/mysql/bin/mysqldumpslow的第161行左右,到底是在操作什么脚本。
156 my @sorted = sort { $stmt{$b}->{$opt{s}} $stmt{$a}->{$opt{s}} } keys %stmt; 157 @sorted = @sorted[0 .. $opt{t}-1] if $opt{t}; 158 @sorted = reverse @sorted if $opt{r}; 159 160 foreach (@sorted) { 161 my $v = $stmt{$_} || die; 162 my ($c, $t,$at, $l,$al, $r,$ar) = @{ $v }{qw(c t at l al r ar)}; 163 my @users = keys %{$v->{users}}; 164 my $user = (@users==1) ? $users[0] : sprintf "%dusers",scalar @users; 165 my @hosts = keys %{$v->{hosts}}; 166 my $host = (@hosts==1) ? $hosts[0] : sprintf "%dhosts",scalar @hosts; 167 printf "Count: %d Time=%.2fs (%ds) Lock=%.2fs (%ds) Rows=%.1f (%d), $user\@$host\n%s\n\n", 168 $c, $at,$t, $al,$l, $ar,$r, $_; 169 } 170 171 sub usage { 172 my $str= shift;
my $v = $stmt{$_} || die;
/usr/local/mysql/bin/mysqldumpslow -s at -t 15 /root/db01-102-slow.log 有 -t 15这一句,那么就是要显示出前15个记录,那么如果我的slow.log统计出来只有12个不到15个,而这里有继续遍历到15的话,那进程肯定会Died。
所以这里有2个解决方法:
1 修改/usr/local/mysql/bin/mysqldumpslow里面的源代码,加null判断。
这个过程有些复杂,暂时略过吧,期待后续空了再研究。
2 修改命令 /usr/local/mysql/bin/mysqldumpslow -s at -t 15 /root/db01-102-slow.log ,把-t 15修改成-t 10或者-t 5试试。
试了好几次,发现临界点在-t 7上面,如下:
[root@slave~]# /usr/local/mysql/bin/mysqldumpslow -s at -t 8 /root/db01-102-slow.log Reading mysql slow query log from /root/db01-102-slow.log Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [dubbo]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [dubbo]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S') Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [xx]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [xx]@[xxx] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [xx]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. -- 临界点 -t 7 [root@db-master-2 ~]# /usr/local/mysql/bin/mysqldumpslow -s at -t 7 /root/db01-102-slow.log Reading mysql slow query log from /root/db01-102-slow.log Count: 22 Time=13.20s (290s) Lock=0.00s (0s) Rows=10.0 (220), [xx]@2hosts select coupon_id, coupon_lot.coupon_lot_id, coupon_lot.remark, coupon.code, coupon_lot.coupon_type, coupon.state, coupon_lot.ckey, coupon_lot.cvalue, coupon_lot.discount, coupon_lot.type, coupon_lot.channel, coupon_lot.is_reusable, coupon_lot.start_datetime, coupon_lot.end_datetime, coupon_lot.create_datetime, coupon.update_datetime ,coupon_lot.department, coupon_lot.state as couponLotState, coupon_lot.create_operator,coupon_lot.coupon_category, coupon_lot.pdt_code,brand.brand_name,product_category.category_name from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id group by coupon_lot.coupon_lot_id order by coupon_lot.create_datetime DESC limit N,N Count: 22 Time=9.61s (211s) Lock=0.00s (0s) Rows=1.0 (22), [dubbo]@2hosts select count(*) from coupon_lot left join coupon on coupon.coupon_lot_id = coupon_lot.coupon_lot_id LEFT JOIN brand ON brand.brand_id=coupon_lot.brand_id LEFT JOIN product_category on product_category.category_id=coupon_lot.category_id Count: 5 Time=2.47s (12s) Lock=0.00s (0s) Rows=0.0 (0), [xx]@2hosts select user_id, usename, nickname, password, user_group_id, realname, gender, email, mobilephone, birthday, province_id, city_id, district_id, marry, income, remarks, create_datetime, active_state, verityEmail, verityPhone, credit, last_login, last_ip, is_locked, channel, tag, union_partner_uuid, union_user_safekey, is_black, qq, weibo_id, verity_email_key, verity_phone_key, verity_email_datetime, verity_phone_datetime, verity_question, verity_answer, cps_code, cps_time_from, cps_time_to, cps_cookie, first_channel from user_info where mobilephone = 'S' and (channel is null or trim(channel) ='S') Count: 177 Time=1.40s (247s) Lock=0.00s (0s) Rows=1.0 (177), [xx]@2hosts select count(*) from user_info LEFT JOIN system_region a ON province_id =a.region_id LEFT JOIN system_region b ON city_id = b.region_id LEFT JOIN system_region c ON district_id = c.region_id Count: 1 Time=1.13s (1s) Lock=0.00s (0s) Rows=10.0 (10), [dubbo]@[xxx] select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC , oi.order_sn limit N,N Count: 8 Time=1.09s (8s) Lock=0.00s (0s) Rows=10.0 (80), [dubbo]@2hosts select return_sn, relating_order_sn, return_from, oi.order_out_sn , add_time , return_type, return_pay, ui.usename as userName, return_consignee, return_goods_count , return_total_fee, total_paid, return_desc, return_order_status, return_pay_status , return_shipping_status, order_return.lock_operator, order_return.return_invoice_no from order_return LEFT JOIN order_info oi on order_return.relating_order_sn = oi.order_sn left join user_info ui on oi.user_id = ui.user_id left join order_payment on order_payment.order_sn = oi.order_sn order by order_return.add_time DESC limit N,N Count: 1 Time=1.00s (1s) Lock=0.00s (0s) Rows=1.0 (1), root[root]@localhost select sleep(N) [root@db-master-2 ~]#
最终总结:
mysqldumpslow报错:Died at /usr/local/mysql/bin/mysqldumpslow line 161, chunk 236. 是因为top数目太多了,mysqldumpslow遍历不过来的缘故。

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Perbezaan antara indeks clustered dan indeks bukan cluster adalah: 1. Klustered Index menyimpan baris data dalam struktur indeks, yang sesuai untuk pertanyaan oleh kunci dan julat utama. 2. Indeks Indeks yang tidak berkumpul indeks nilai utama dan penunjuk kepada baris data, dan sesuai untuk pertanyaan lajur utama bukan utama.

MySQL dan Mariadb boleh wujud bersama, tetapi perlu dikonfigurasikan dengan berhati -hati. Kuncinya adalah untuk memperuntukkan nombor port dan direktori data yang berbeza untuk setiap pangkalan data, dan menyesuaikan parameter seperti peruntukan memori dan saiz cache. Konfigurasi sambungan, konfigurasi aplikasi, dan perbezaan versi juga perlu dipertimbangkan dan perlu diuji dengan teliti dan dirancang untuk mengelakkan perangkap. Menjalankan dua pangkalan data secara serentak boleh menyebabkan masalah prestasi dalam situasi di mana sumber terhad.

Dalam pangkalan data MySQL, hubungan antara pengguna dan pangkalan data ditakrifkan oleh kebenaran dan jadual. Pengguna mempunyai nama pengguna dan kata laluan untuk mengakses pangkalan data. Kebenaran diberikan melalui perintah geran, sementara jadual dibuat oleh perintah membuat jadual. Untuk mewujudkan hubungan antara pengguna dan pangkalan data, anda perlu membuat pangkalan data, membuat pengguna, dan kemudian memberikan kebenaran.

MySQL menyokong empat jenis indeks: B-Tree, Hash, Full-Text, dan Spatial. 1. B-Tree Index sesuai untuk carian nilai yang sama, pertanyaan dan penyortiran. 2. Indeks hash sesuai untuk carian nilai yang sama, tetapi tidak menyokong pertanyaan dan penyortiran pelbagai. 3. Indeks teks penuh digunakan untuk carian teks penuh dan sesuai untuk memproses sejumlah besar data teks. 4. Indeks spatial digunakan untuk pertanyaan data geospatial dan sesuai untuk aplikasi GIS.
