Search Results

Search found 9233 results on 370 pages for 'high school'.

Page 44/370 | < Previous Page | 40 41 42 43 44 45 46 47 48 49 50 51  | Next Page >

  • Why does my HDD produce a high-pitched noise when the CPU is in use?

    - by CyberOptic
    I know this is strange. Some time ago, I bought a new 7200rpm HDD for my desktop system (I'll look for the model later). Every time the CPU is used, a high frequency cheep comes from the HDD. I'm sure it's the HDD because the problem does not occur if the HDD is not attached or is in energy-saving mode (I cross-checked by booting from a live CD). What could be the reason for the cheep sounds? Could it be the power supply?

    Read the article

  • how do i design a high pass filters in matlab without using the builtin function?

    - by noura
    hello everyone, i'm just not sure how to draw the frequency response (H) of the high pass filter? after drawing the frequency response i can get the b coefficient by taking the ifft of (H). so yeah, for a low pass filter, with a cutoff frequency of say pi/2 : the frequency response code will be H = exp(-1*j*w*4).*(((0 <= w) & (w<= pi/2)) | ((2*pi - pi/2 <= w) & (w<=2*pi)); sincr the response is "1" between 0 and pi/2 and between (2*pi - pi/2) and 2*pi. can you help me write H for a high pass filter? thanx in advance.

    Read the article

  • Is the 'var' keyword bad? Or am I just old school?

    - by WaggingSiberian
    Recently I overheard junior developer ask "why do you use 'var' so much?". The mid-level developer responded "I use VAR all the time. I love it! I don't have to figure out the type." I didn't have the time or energy to get into a religious war and hey, I'm still the new guy here :-) I understand var has its place. LINQ comes to mind. But I have also always been told the use of var represents lazy programming and I should just use the correct type to begin with. If it's an int, define it as an int, not a var. When reviewing code, seeing the type makes it easier to follow. My opinion is, it's just lazy but there are exceptions. Var also reminds me of the VB/VBA variant type. It also had its place. I recall (from many years ago) its usage being less-than-desirable type and it was rather resource hungry. Am I just being stuck in my ways? Should we start using var all the time as my co-worker does?

    Read the article

  • Why is the 'var' keyword bad? Or am I just old school?

    - by WaggingSiberian
    Recently I overheard junior developer ask "why do you use 'var' so much?". The mid-level developer responded "I use VAR all the time. I love it! I don't have to figure out the type." I didn't have the time or energy to get into a religious war and hey, I'm still the new guy here :-) I understand var has its place. LINQ comes to mind. But I have also always been told the use of var represents lazy programming and I should just use the correct type to begin with. If it's an int, define it as an int, not a var. When reviewing code, seeing the type makes it easier to follow. My opinion is, it's just lazy but there are exception. Var also reminds me of the VB/VBA variant type. It also had its place. I recall (from many years ago) its usage being less-than-desirable type and it was rather resource hungry. Am I just being stuck in my ways? Should we start using var all the time as my co-worker does?

    Read the article

  • Will the next iPhone Simulator be able to simulate the high resolution of iPhone 4?

    - by dontWatchMyProfile
    As a follow-up to this question, the next one is: Will we be able to simulate our interfaces how they look on the new high resolution display, even without owning an iPhone 4? I guess that there is a formula that we can use to calculate the exact needed distance between our monitors and our eyes, to achieve the exact same visual effect of the Retina Display. This would help a lot to get things right. The first thing we need is an high resolution iPhone Simulator. I can't get any sleep until I know.

    Read the article

  • How use DNS server to create simple HA (High availability) of my website?

    - by marc22
    Welcome, How can i use DNS server to create simple HA (High availability) of website ? For example if my web-server ( for better understanding i use internal IP in real it will be other hosting companies) 192.168.0.120 :80 (is offline) traffic go to 192.168.0.130 :80 You have right, i use bad word "hight avability" of course i was thinking about failover. Using few IP in A records is good for simple load-balancing. But not in case, if i want notice user about failure (for example display page, Oops something is wrong without our server, we working on it) against "can't establish connection". I was thinking about setting up something like this 2 DNS servers, one installed on www server Both have low TTL on my domain, set up 2 ns records first for DNS with my apache server second to other dns If user try connect he will get ip of www server using first dns, if that dns is offline (probably www server is also down) so it will try second NS record, what will point to another dns, that dns will point to "backup" page. That's what i would like to do. If You have other idea please share. Reverse proxy is not option, because IP of server can change, or i can use other country for backup.

    Read the article

  • Server load high, CPU idle. NFS the cause?

    - by Mech Software
    I am running into a scenario where I'm seeing a high server load (sometimes upwards of 20 or 30) and a very low CPU usage (98% idle). I'm wondering if these wait states are coming as part of an NFS filesystem connection. Here is what I see in VMStat procs -----------memory---------- ---swap-- -----io---- --system-- -----cpu------ r b swpd free buff cache si so bi bo in cs us sy id wa st 2 1 0 1298784 0 0 0 0 16 5 0 9 1 1 97 2 0 0 1 0 1308016 0 0 0 0 0 0 0 3882 4 3 80 13 0 0 1 0 1307960 0 0 0 0 120 0 0 2960 0 0 88 12 0 0 1 0 1295868 0 0 0 0 4 0 0 4235 1 2 84 13 0 6 0 0 1292740 0 0 0 0 0 0 0 5003 1 1 98 0 0 4 0 0 1300860 0 0 0 0 0 120 0 11194 4 3 93 0 0 4 1 0 1304576 0 0 0 0 240 0 0 11259 4 3 88 6 0 3 1 0 1298952 0 0 0 0 0 0 0 9268 7 5 70 19 0 3 1 0 1303740 0 0 0 0 88 8 0 8088 4 3 81 13 0 5 0 0 1304052 0 0 0 0 0 0 0 6348 4 4 93 0 0 0 0 0 1307952 0 0 0 0 0 0 0 7366 5 4 91 0 0 0 0 0 1307744 0 0 0 0 0 0 0 3201 0 0 100 0 0 4 0 0 1294644 0 0 0 0 0 0 0 5514 1 2 97 0 0 3 0 0 1301272 0 0 0 0 0 0 0 11508 4 3 93 0 0 3 0 0 1307788 0 0 0 0 0 0 0 11822 5 3 92 0 0 From what I can tell when the IO goes up the waits go up. Could NFS be the cause here or should I be worried about something else? This is a VPS box on a fiber channel SAN. I'd think the bottleneck wouldn't be the SAN. Comments?

    Read the article

  • Does a high run queue length average result in poor performance for a web server?

    - by Domino
    I'm trying to narrow down the list of suspects of web servers that perform moderately well most of the time with occasional bouts of poor performance. I'm analyzing the data collected and summarized by sar. I've noticed a few things, one of which is high number of tasks in the run queue. 10:15:01 AM runq-sz plist-sz ldavg-1 ldavg-5 ldavg-15 blocked 10:25:01 AM 2 150 0.05 0.05 0.06 0 10:35:01 AM 4 149 0.08 0.12 0.09 0 10:45:01 AM 6 150 0.13 0.19 0.15 0 10:55:01 AM 1 150 0.08 0.10 0.13 0 11:05:01 AM 4 150 0.20 0.35 0.23 0 11:15:01 AM 3 149 0.02 0.09 0.15 0 11:25:01 AM 7 149 0.04 0.05 0.11 0 11:35:01 AM 4 150 0.14 0.15 0.13 0 11:45:01 AM 6 150 0.27 0.18 0.16 0 11:55:01 AM 5 150 0.08 0.10 0.13 0 12:05:01 PM 3 149 0.35 0.40 0.26 0 12:15:01 PM 19 155 0.02 0.10 0.16 1 12:25:01 PM 2 150 0.00 0.07 0.12 0 12:35:02 PM 3 151 0.58 0.24 0.17 0 12:45:01 PM 8 150 0.02 0.13 0.15 0 12:55:01 PM 6 149 0.81 0.29 0.18 0 01:05:01 PM 3 148 0.00 0.09 0.13 0 01:15:01 PM 7 149 0.00 0.04 0.11 0 I believe these are 10 minute averages. Is this an indicator that the web server is not performing as fast as it could if the average run queue length was lower?

    Read the article

  • Using a secondary DNS when lookup fails in primary? [migrated]

    - by Huckle
    I use a VPN to connect my development machine to my school's CS dept. The development machine is Ubuntu as we do C programming in Unix. I used vpnc to do that. The school uses some DNS entries that only resolve on their DNS servers, i.e., internalserver.csdept.school.edu I am normally attached to the VPN whenever booted for convenience. However I noticed the other day that when I disconnect the VPN all my DNS queries fail. This obviously means that vpnc set up the school's DNS to be used. However I'd rather not use their DNS all the time (tracking and privacy and whatnot). Is there a way I can restore my ISP's DNS and then if the lookup fails, have it use my school's DNS?

    Read the article

  • No database selected error in CodeIgniter running on MAMP stack

    - by Apophenia Overload
    First off, does anyone know of a good place to get help with CodeIgniter? The official community forums are somewhat disappointing in terms of getting many responses. I have ci installed on a regular MAMP stack, and I’m working on this tutorial. However, I have only gone through the Created section, and currently I am getting a No database selected error. Model: <?php class submit_model extends Model { function submitForm($school, $district) { $data = array( 'school' => $school, 'district' => $district ); $this->db->insert('your_stats', $data); } } View: <?php $this->load->helper('form'); ?> <?php echo form_open('main'); ?> <p> <?php echo form_input('school'); ?> </p> <p> <?php echo form_input('district'); ?> </p> <p> <?php echo form_submit('submit', 'Submit'); ?> </p> <?php echo form_close(); ?> Controller: <?php class Main extends controller { function index() { // Check if form is submitted if ($this->input->post('submit')) { $school = $this->input->xss_clean($this->input->post('school')); $district = $this->input->xss_clean($this->input->post('district')); $this->load->model('submit_model'); // Add the post $this->submit_model->submitForm($school, $district); } $this->load->view('main_view'); } } database.php $db['default']['hostname'] = "localhost:8889"; $db['default']['username'] = "root"; $db['default']['password'] = "root"; $db['default']['database'] = "stats_test"; $db['default']['dbdriver'] = "mysql"; $db['default']['dbprefix'] = ""; $db['default']['pconnect'] = TRUE; $db['default']['db_debug'] = TRUE; $db['default']['cache_on'] = FALSE; $db['default']['cachedir'] = ""; $db['default']['char_set'] = "utf8"; $db['default']['dbcollat'] = "utf8_general_ci"; config.php $config['base_url'] = "http://localhost:8888/ci/"; ... $config['index_page'] = "index.php"; ... $config['uri_protocol'] = "AUTO"; So, how come it’s giving me this error message? A Database Error Occurred Error Number: 1046 No database selected INSERT INTO `your_stats` (`school`, `district`) VALUES ('TJHSST', 'FairFax') Is there any way for me to test if CodeIgniter can actually detect the mySQL databases I've created with phpMyAdmin in my MAMP stack?

    Read the article

  • administraitor denies command prompt

    - by roxas383
    I looked at the command prompt faqs on this webiste and tried to get me to make a new profile but when i went to open it it said "The command prompt has been disabled by your administraitor-click any key to countinue" and when i do it closes which i knew that was going to happen. Is there someway i can stop the admin from blocking my command prompt? oh and i was at school too (Dont know if this helps but i am in the West Allis West Milwaukee school district). Also, is there a way i can hack into the blocking program for my school at all? I don't remember what the program is but it might have to do with vision? I'm not sure but it would be greatly appreciated if someone could help (could i download a program on a flash drive that denies any blocking and/or disabling SafeSearch and plug it in into a computer at my school and use it from the flash drive? Would the school blocking thingy deny it from working?) HELP ME PLEASE!!!!!!!!!

    Read the article

  • cant get ubuntu to work with windows 8

    - by John Mark High
    ive been trying to dual boot Ubuntu with windows 8 but so far I haven't been able too. the laptop im using is a HP Pavilion g6-2240sa pre-installed with windows 8. ive made the bootbale USB with Ubuntu 12.10, it installs but when I restart the computer boot straight into windows, no grub boot options. I can get into Ubuntu once by doing an advanced restart and booting from the Ubuntu partition. I can use Ubuntu fine but once I restart or shutdown, I do the advanced restart again and the Ubuntu partition is now gone and I have to reinstall. i used this tutorial to install Ubuntu, http://www.youtube.com/watch?v=wNCSbTyUzoM After i have to reinstall and still no grub boot menu, i used the boot repair to re-install it. once i rebooted the computer it went straight to windows again and the Ubuntu partition was gone. can i dual boot windows 8 and unbuntu 12.10 with the grub so i can pick what OS to boot into when the computer is starting, and without the partition going AWOL???? Thanks in advance

    Read the article

  • Partition Table and Exadata Hybrid Columnar Compression (EHCC)

    - by Bandari Huang
    Create EHCC table CREATE TABLE ... COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH]; select owner,table_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ‘ENABLED'; Convert Table/Partition/Subpartition to EHCC Compress Table&Partition&Subpartition to EHCC: ALTER TABLE table_name MOVE COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH] [PARALLEL <dop>]; ALTER TABLE table_name MOVE PARATITION partition_name COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH] [PARALLEL <dop>]; ALTER TABLE table_name MOVE SUBPARATITION subpartition_name COMPRESS FOR [QUERY LOW|QUERY HIGH|ARCHIVE LOW|ARCHIVE HIGH] [PARALLEL <dop>]; select owner,table_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ‘ENABLED'; select table_owner,table_name,partition_name,compress_for DBA_TAB_PARTITIONS where compression = ‘ENABLED’; select table_owner,table_name,subpartition_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ‘ENABLED’; Rebuild Unusable Index: select index_name from dba_index where status = 'UNUSABLE'; select index_name,partition_name from dba_ind_partition where status = 'UNUSABLE'; select index_name,subpartition_name from dba_ind_partition where status = 'UNUSABLE'; ALTER INDEX index_name REBUILD [PARALLEL <dop>]; ALTER INDEX index_name REBUILD PARTITION partition_name [PARALLEL <dop>]; ALTER INDEX index_name REBUILD SUBPARTITION subpartition_name [PARALLEL <dop>]; Convert Table/Partition/Subpartition from EHCC to OLTP compression or uncompressed format: Uncompress EHCC Table&Partition&Subpartition: ALTER TABLE table_name MOVE [NOCOMPRESS|COMPRESS for OLTP] [PARALLEL <dop>]; ALTER TABLE table_name MOVE PARTITION partition_name [NOCOMPRESS|COMPRESS for OLTP] [PARALLEL <dop>]; ALTER TABLE table_name MOVE SUBPARTITION subpartition_name [NOCOMPRESS|COMPRESS for OLTP] [PARALLEL <dop>]; select owner,table_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ''; select table_owner,table_name,partition_name,compress_for DBA_TAB_PARTITIONS where compression = ''; select table_owner,table_name,subpartition_name,compress_for DBA_TAB_SUBPARTITIONS where compression = ''; Rebuild Unusable Index: select index_name from dba_index where status = 'UNUSABLE'; select index_name,partition_name from dba_ind_partition where status = 'UNUSABLE'; select index_name,subpartition_name from dba_ind_partition where status = 'UNUSABLE'; ALTER INDEX index_name REBUILD [PARALLEL <dop>]; ALTER INDEX index_name REBUILD PARTITION partition_name [PARALLEL <dop>]; ALTER INDEX index_name REBUILD SUBPARTITION subpartition_name [PARALLEL <dop>];

    Read the article

  • Ubuntu 12.10 wont boot

    - by John Mark High
    im new to using Ubuntu and just bought a HP Pavilion g6-2240sa with windows 8 pre installed. I made a bootable USB with Ubuntu on it and installed alsongside windows, for 2 days it worked fine, I got into Ubuntu by doing an advanced restart from windows 8 and then booting Ubuntu from the partition it made. When i did the advanced restart today there was only 1 HDD i could select ( there were 3 before windows, a restore partition that was already there when i got the computer and Ubuntu) so i booted from the USB again and re-installed Ubuntu. then did an advanced restart and the 3 partitions where there again, i booted from Ubuntu and now heres my problem. I get the Ubuntu background when its loading then its just a black screen with some writing, its not on long enough to read, then just a black screen with a white _ and the top left corner that does nothing, i have to restat the computer and it auto boots into windows 8. im a little confused as the first time i installed Ubuntu it worked fine until the partition dissaperd), the second time i installed i did everything the same except it found the old Ubuntu so i reinstalled it and now is donst work.

    Read the article

  • usb drive filesystem?

    - by purbleguy
    So, school is approaching quickly, and one of the things on my supply list is a usb drive. Now I'm asking myself what filesystem to use. After some research, I found ext4 to be the most stable drive filesystem. But, I also found that Windows (The OS used by every computer in my school) can't read ext4 formatted drives without special drivers, and I'm sure the school wouldn't be too happy with me having to install the windows ext4 drivers on every computer I use with my usb. So, my question is, Should I use fat32, one of the ext filesystems (2, 3 or 4 would work) or NTFS, I have an ubuntu laptop, a Mac desktop, and of course the school computers I use are Windows, so which would be the best filesystem for my usb.

    Read the article

  • How to Get the Best Search Engine Placement

    Search engine placement is very important for a successful internet marketing affair. Everyone prefers that their site figure high on the search listings. It is also of high priority that they figure high on search engines as the customer will surely be influenced by the top ten results displayed on a search page. There are many things that have to be taken a note of when looking to get a high ranking. What is required is a balance between quality and quantity.

    Read the article

  • Improving TCP performance over a gigabit network with lots of connections and high traffic of small packets

    - by MinimeDJ
    I’m trying to improve my TCP throughput over a “gigabit network with lots of connections and high traffic of small packets”. My server OS is Ubuntu 11.10 Server 64bit. There are about 50.000 (and growing) clients connected to my server through TCP Sockets (all on the same port). 95% of of my packets have size of 1-150 bytes (TCP header and payload). The rest 5% vary from 150 up to 4096+ bytes. With the config below my server can handle traffic up to 30 Mbps (full duplex). Can you please advice best practice to tune OS for my needs? My /etc/sysctl.cong looks like this: kernel.pid_max = 1000000 net.ipv4.ip_local_port_range = 2500 65000 fs.file-max = 1000000 # net.core.netdev_max_backlog=3000 net.ipv4.tcp_sack=0 # net.core.rmem_max = 16777216 net.core.wmem_max = 16777216 net.core.somaxconn = 2048 # net.ipv4.tcp_rmem = 4096 87380 16777216 net.ipv4.tcp_wmem = 4096 65536 16777216 # net.ipv4.tcp_synack_retries = 2 net.ipv4.tcp_syncookies = 1 net.ipv4.tcp_mem = 50576 64768 98152 # net.core.wmem_default = 65536 net.core.rmem_default = 65536 net.ipv4.tcp_window_scaling=1 # net.ipv4.tcp_mem= 98304 131072 196608 # net.ipv4.tcp_timestamps = 0 net.ipv4.tcp_rfc1337 = 1 net.ipv4.ip_forward = 0 net.ipv4.tcp_congestion_control=cubic net.ipv4.tcp_tw_recycle = 0 net.ipv4.tcp_tw_reuse = 0 # net.ipv4.tcp_orphan_retries = 1 net.ipv4.tcp_fin_timeout = 25 net.ipv4.tcp_max_orphans = 8192 Here are my limits: $ ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 193045 max locked memory (kbytes, -l) 64 max memory size (kbytes, -m) unlimited open files (-n) 1000000 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 8192 cpu time (seconds, -t) unlimited max user processes (-u) 1000000 [ADDED] My NICs are the following: $ dmesg | grep Broad [ 2.473081] Broadcom NetXtreme II 5771x 10Gigabit Ethernet Driver bnx2x 1.62.12-0 (2011/03/20) [ 2.477808] bnx2x 0000:02:00.0: eth0: Broadcom NetXtreme II BCM57711E XGb (A0) PCI-E x4 5GHz (Gen2) found at mem fb000000, IRQ 28, node addr d8:d3:85:bd:23:08 [ 2.482556] bnx2x 0000:02:00.1: eth1: Broadcom NetXtreme II BCM57711E XGb (A0) PCI-E x4 5GHz (Gen2) found at mem fa000000, IRQ 40, node addr d8:d3:85:bd:23:0c [ADDED 2] ethtool -k eth0 Offload parameters for eth0: rx-checksumming: on tx-checksumming: on scatter-gather: on tcp-segmentation-offload: on udp-fragmentation-offload: off generic-segmentation-offload: on generic-receive-offload: on large-receive-offload: on rx-vlan-offload: on tx-vlan-offload: on ntuple-filters: off receive-hashing: off [ADDED 3] sudo ethtool -S eth0|grep -vw 0 NIC statistics: [1]: rx_bytes: 17521104292 [1]: rx_ucast_packets: 118326392 [1]: tx_bytes: 35351475694 [1]: tx_ucast_packets: 191723897 [2]: rx_bytes: 16569945203 [2]: rx_ucast_packets: 114055437 [2]: tx_bytes: 36748975961 [2]: tx_ucast_packets: 194800859 [3]: rx_bytes: 16222309010 [3]: rx_ucast_packets: 109397802 [3]: tx_bytes: 36034786682 [3]: tx_ucast_packets: 198238209 [4]: rx_bytes: 14884911384 [4]: rx_ucast_packets: 104081414 [4]: rx_discards: 5828 [4]: rx_csum_offload_errors: 1 [4]: tx_bytes: 35663361789 [4]: tx_ucast_packets: 194024824 [5]: rx_bytes: 16465075461 [5]: rx_ucast_packets: 110637200 [5]: tx_bytes: 43720432434 [5]: tx_ucast_packets: 202041894 [6]: rx_bytes: 16788706505 [6]: rx_ucast_packets: 113123182 [6]: tx_bytes: 38443961940 [6]: tx_ucast_packets: 202415075 [7]: rx_bytes: 16287423304 [7]: rx_ucast_packets: 110369475 [7]: rx_csum_offload_errors: 1 [7]: tx_bytes: 35104168638 [7]: tx_ucast_packets: 184905201 [8]: rx_bytes: 12689721791 [8]: rx_ucast_packets: 87616037 [8]: rx_discards: 2638 [8]: tx_bytes: 36133395431 [8]: tx_ucast_packets: 196547264 [9]: rx_bytes: 15007548011 [9]: rx_ucast_packets: 98183525 [9]: rx_csum_offload_errors: 1 [9]: tx_bytes: 34871314517 [9]: tx_ucast_packets: 188532637 [9]: tx_mcast_packets: 12 [10]: rx_bytes: 12112044826 [10]: rx_ucast_packets: 84335465 [10]: rx_discards: 2494 [10]: tx_bytes: 36562151913 [10]: tx_ucast_packets: 195658548 [11]: rx_bytes: 12873153712 [11]: rx_ucast_packets: 89305791 [11]: rx_discards: 2990 [11]: tx_bytes: 36348541675 [11]: tx_ucast_packets: 194155226 [12]: rx_bytes: 12768100958 [12]: rx_ucast_packets: 89350917 [12]: rx_discards: 2667 [12]: tx_bytes: 35730240389 [12]: tx_ucast_packets: 192254480 [13]: rx_bytes: 14533227468 [13]: rx_ucast_packets: 98139795 [13]: tx_bytes: 35954232494 [13]: tx_ucast_packets: 194573612 [13]: tx_bcast_packets: 2 [14]: rx_bytes: 13258647069 [14]: rx_ucast_packets: 92856762 [14]: rx_discards: 3509 [14]: rx_csum_offload_errors: 1 [14]: tx_bytes: 35663586641 [14]: tx_ucast_packets: 189661305 rx_bytes: 226125043936 rx_ucast_packets: 1536428109 rx_bcast_packets: 351 rx_discards: 20126 rx_filtered_packets: 8694 rx_csum_offload_errors: 11 tx_bytes: 548442367057 tx_ucast_packets: 2915571846 tx_mcast_packets: 12 tx_bcast_packets: 2 tx_64_byte_packets: 35417154 tx_65_to_127_byte_packets: 2006984660 tx_128_to_255_byte_packets: 373733514 tx_256_to_511_byte_packets: 378121090 tx_512_to_1023_byte_packets: 77643490 tx_1024_to_1522_byte_packets: 43669214 tx_pause_frames: 228 Some info about SACK: When to turn TCP SACK off?

    Read the article

  • Searching with MATCH(), AGAINST() and AS score with mysqli and php

    - by Drew
    Below is the code I am using to search my table. I have made the relevant columns FULLTEXT in the table. This doesn't return me anything. Can someone tell me what it is that i'm doing wrong? Thanks in advance. $sql = 'SELECT id,uname,class,school, MATCH(uname, class, school) AGAINST(?) AS score FROM images WHERE MATCH(uname, class, school) AGAINST(? IN BOOLEAN MODE) ORDER BY score DES'; $stmt = $db_connection->prepare($sql); $stmt->bind_param('ss',$keyword,$keyword); $stmt->execute(); $stmt->store_result(); $stmt->bind_result($id,$uname,$class,$school); $xml = "<data>".PHP_EOL; while($stmt->fetch()){ $xml .= " <person>".PHP_EOL; $xml .= " <id>$id</id>".PHP_EOL; $xml .= " <name>$uname</name>".PHP_EOL; $xml .= " <class>$class</class>".PHP_EOL; $xml .= " <school>$school</school>".PHP_EOL; $xml .= " </person>".PHP_EOL; } $xml .= "</data>"; echo $xml; Below is an image of the indexes of the table:

    Read the article

  • many to many relationship mysql select

    - by zeina
    Let's consider 2 tables "schools" and "students". Now a student may belong to different schools in his life, and a school have many students. So this is a many to many example. A third table "links" specify the relation between student and school. Now to query this I do the following: Select sc.sid , -- stands for school id st.uid, -- stands for student id sc.sname, -- stands for school name st.uname, -- stands for student name -- select more data about the student joining other tables for that from students s left join links l on l.uid=st.uid -- l.uid stands for the student id on the links table left join schools sc on sc.sid=l.sid -- l.sid is the id of the school in the links table where st.uid=3 -- 3 is an example this query will return duplicate data for the user id if he has more than one school, so to fix this I added group by st.uid, yet I also need the list of school name related to the same user. Is there a way to do it with fixing the query I wrote instead of having 2 queries? So as example I want to have Luci of schools ( X, Y, Z, R, ...) etc

    Read the article

  • What is causing the unusual high load average and IOwait?

    - by James
    I noticed on Tuesday night of last week, the load average went up sharply and it seemed abnormal since the traffic is small. Usually, the numbers usually average around .40 or lower and my server stuff (mysql, php and apache) are optimized. I noticed that the IOWait is unusually high even though the processes is barely using any CPU. top - 01:44:39 up 1 day, 21:13, 1 user, load average: 1.41, 1.09, 0.86 Tasks: 60 total, 1 running, 59 sleeping, 0 stopped, 0 zombie Cpu0 : 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Cpu1 : 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Cpu2 : 0.0%us, 0.3%sy, 0.0%ni, 99.7%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Cpu3 : 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Cpu4 : 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Cpu5 : 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Cpu6 : 0.0%us, 0.0%sy, 0.0%ni,100.0%id, 0.0%wa, 0.0%hi, 0.0%si, 0.0%st Cpu7 : 0.0%us, 0.0%sy, 0.0%ni, 91.5%id, 8.5%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 1048576k total, 331944k used, 716632k free, 0k buffers Swap: 0k total, 0k used, 0k free, 0k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1 root 15 0 2468 1376 1140 S 0 0.1 0:00.92 init 1656 root 15 0 13652 5212 664 S 0 0.5 0:00.00 apache2 9323 root 18 0 13652 5212 664 S 0 0.5 0:00.00 apache2 10079 root 18 0 3972 1248 972 S 0 0.1 0:00.00 su 10080 root 15 0 4612 1956 1448 S 0 0.2 0:00.01 bash 11298 root 15 0 13652 5212 664 S 0 0.5 0:00.00 apache2 11778 chikorit 15 0 2344 1092 884 S 0 0.1 0:00.05 top 15384 root 18 0 17544 13m 1568 S 0 1.3 0:02.28 miniserv.pl 15585 root 15 0 8280 2736 2168 S 0 0.3 0:00.02 sshd 15608 chikorit 15 0 8280 1436 860 S 0 0.1 0:00.02 sshd Here is the VMStat procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 1 0 0 768644 0 0 0 0 14 23 0 10 1 0 99 0 IOStat - Nothing unusal Total DISK READ: 67.13 K/s | Total DISK WRITE: 0.00 B/s TID PRIO USER DISK READ DISK WRITE SWAPIN IO COMMAND 19496 be/4 chikorit 11.85 K/s 0.00 B/s 0.00 % 0.00 % apache2 -k start 19501 be/4 mysql 3.95 K/s 0.00 B/s 0.00 % 0.00 % mysqld 19568 be/4 chikorit 11.85 K/s 0.00 B/s 0.00 % 0.00 % apache2 -k start 19569 be/4 chikorit 11.85 K/s 0.00 B/s 0.00 % 0.00 % apache2 -k start 19570 be/4 chikorit 11.85 K/s 0.00 B/s 0.00 % 0.00 % apache2 -k start 19571 be/4 chikorit 7.90 K/s 0.00 B/s 0.00 % 0.00 % apache2 -k start 19573 be/4 chikorit 7.90 K/s 0.00 B/s 0.00 % 0.00 % apache2 -k start 1 be/4 root 0.00 B/s 0.00 B/s 0.00 % 0.00 % init 11778 be/4 chikorit 0.00 B/s 0.00 B/s 0.00 % 0.00 % top 19470 be/4 mysql 0.00 B/s 0.00 B/s 0.00 % 0.00 % mysqld Load Average Chart - http://i.stack.imgur.com/kYsD0.png I want to be sure if this is not a MySQL problem before making sure. Also, this is a Ubuntu 10.04 LTS Server on OpenVZ. Edit: This will probably give a good picture on the IO Wait top - 22:12:22 up 17:41, 1 user, load average: 1.10, 1.09, 0.93 Tasks: 33 total, 1 running, 32 sleeping, 0 stopped, 0 zombie Cpu(s): 0.6%us, 0.2%sy, 0.0%ni, 89.0%id, 10.1%wa, 0.0%hi, 0.0%si, 0.0%st Mem: 1048576k total, 260708k used, 787868k free, 0k buffers Swap: 0k total, 0k used, 0k free, 0k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 1 root 15 0 2468 1376 1140 S 0 0.1 0:00.88 init 5849 root 15 0 12336 4028 668 S 0 0.4 0:00.00 apache2 8063 root 15 0 12336 4028 668 S 0 0.4 0:00.00 apache2 9732 root 16 0 8280 2728 2168 S 0 0.3 0:00.02 sshd 9746 chikorit 18 0 8412 1444 864 S 0 0.1 0:01.10 sshd 9747 chikorit 18 0 4576 1960 1488 S 0 0.2 0:00.24 bash 13706 chikorit 15 0 2344 1088 884 R 0 0.1 0:00.03 top 15745 chikorit 15 0 12968 5108 1280 S 0 0.5 0:00.00 apache2 15751 chikorit 15 0 72184 25m 18m S 0 2.5 0:00.37 php5-fpm 15790 chikorit 18 0 12472 4640 1192 S 0 0.4 0:00.00 apache2 15797 chikorit 15 0 72888 23m 16m S 0 2.3 0:00.06 php5-fpm 16038 root 15 0 67772 2848 592 D 0 0.3 0:00.00 php5-fpm 16309 syslog 18 0 24084 1316 992 S 0 0.1 0:00.07 rsyslogd 16316 root 15 0 5472 908 500 S 0 0.1 0:00.00 sshd 16326 root 15 0 2304 908 712 S 0 0.1 0:00.02 cron 17464 root 15 0 10252 7560 856 D 0 0.7 0:01.88 psad 17466 root 18 0 1684 276 208 S 0 0.0 0:00.31 psadwatchd 17559 root 18 0 11444 2020 732 S 0 0.2 0:00.47 sendmail-mta 17688 root 15 0 10252 5388 1136 S 0 0.5 0:03.81 python 17752 teamspea 19 0 44648 7308 4676 S 0 0.7 1:09.70 ts3server_linux 18098 root 15 0 12336 6380 3032 S 0 0.6 0:00.47 apache2 18099 chikorit 18 0 10368 2536 464 S 0 0.2 0:00.00 apache2 18120 ntp 15 0 4336 1316 984 S 0 0.1 0:00.87 ntpd 18379 root 15 0 12336 4028 668 S 0 0.4 0:00.00 apache2 18387 mysql 15 0 62796 36m 5864 S 0 3.6 1:43.26 mysqld 19584 root 15 0 12336 4028 668 S 0 0.4 0:00.02 apache2 22498 root 16 0 12336 4028 668 S 0 0.4 0:00.00 apache2 24260 root 15 0 67772 3612 1356 S 0 0.3 0:00.22 php5-fpm 27712 root 15 0 12336 4028 668 S 0 0.4 0:00.00 apache2 27730 root 15 0 12336 4028 668 S 0 0.4 0:00.00 apache2 30343 root 15 0 12336 4028 668 S 0 0.4 0:00.00 apache2 30366 root 15 0 12336 4028 668 S 0 0.4 0:00.00 apache2

    Read the article

  • Improving TCP performance over a gigabit network lots of connections and high traffic for storage and streaming services

    - by Linux Guy
    I have two servers, Both servers hardware Specification are Processor : Dual Processor RAM : over 128 G.B Hard disk : SSD Hard disk Outging Traffic bandwidth : 3 Gbps network cards speed : 10 Gbps Server A : for Encoding videos Server B : for storage videos andstream videos over web interface like youtube The inbound bandwidth between two servers is 10Gbps , the outbound bandwidth internet bandwidth is 500Mpbs Both servers using public ip addresses in public and private network Both servers transfer and connection on nginx port , and the server B used for streaming media , like youtube stream videos Both servers in same network , when i do ping from Server A to Server B i got high time latency above 1.0ms , the time range time=52.7 ms to time=215.7 ms - This is the output of iftop utility 353Mb 707Mb 1.04Gb 1.38Gb 1.73Gb mqqqqqqqqqqqqqqqqqqqqqqqqqqqvqqqqqqqqqqqqqqqqqqqqqqqqqqqvqqqqqqqqqqqqqqqqqqqqqqqqqqqvqqqqqqqqqqqqqqqqqqqqqqqqqqqvqqqqqqqqqqqqqqqqqqqqqqqqqqq server.example.com => ip.address 6.36Mb 4.31Mb 1.66Mb <= 158Kb 94.8Kb 35.1Kb server.example.com => ip.address 1.23Mb 4.28Mb 1.12Mb <= 17.1Kb 83.5Kb 21.9Kb server.example.com => ip.address 395Kb 3.89Mb 1.07Mb <= 6.09Kb 109Kb 28.6Kb server.example.com => ip.address 4.55Mb 3.83Mb 1.04Mb <= 55.6Kb 45.4Kb 13.0Kb server.example.com => ip.address 649Kb 3.38Mb 1.47Mb <= 9.00Kb 38.7Kb 16.7Kb server.example.com => ip.address 5.00Mb 3.32Mb 1.80Mb <= 65.7Kb 55.1Kb 29.4Kb server.example.com => ip.address 387Kb 3.13Mb 1.06Mb <= 18.4Kb 39.9Kb 15.0Kb server.example.com => ip.address 3.27Mb 3.11Mb 1.01Mb <= 81.2Kb 64.5Kb 20.9Kb server.example.com => ip.address 1.75Mb 3.08Mb 2.72Mb <= 16.6Kb 35.6Kb 32.5Kb server.example.com => ip.address 1.75Mb 2.90Mb 2.79Mb <= 22.4Kb 32.6Kb 35.6Kb server.example.com => ip.address 3.03Mb 2.78Mb 1.82Mb <= 26.6Kb 27.4Kb 20.2Kb server.example.com => ip.address 2.26Mb 2.66Mb 1.36Mb <= 51.7Kb 49.1Kb 24.4Kb server.example.com => ip.address 586Kb 2.50Mb 1.03Mb <= 4.17Kb 26.1Kb 10.7Kb server.example.com => ip.address 2.42Mb 2.49Mb 2.44Mb <= 31.6Kb 29.7Kb 29.9Kb server.example.com => ip.address 2.41Mb 2.46Mb 2.41Mb <= 26.4Kb 24.5Kb 23.8Kb server.example.com => ip.address 2.37Mb 2.39Mb 2.40Mb <= 28.9Kb 27.0Kb 28.5Kb server.example.com => ip.address 525Kb 2.20Mb 1.05Mb <= 7.03Kb 26.0Kb 12.8Kb qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq TX: cum: 102GB peak: 1.65Gb rates: 1.46Gb 1.44Gb 1.48Gb RX: 1.31GB 24.3Mb 19.5Mb 18.9Mb 20.0Mb TOTAL: 103GB 1.67Gb 1.48Gb 1.46Gb 1.50Gb I check the transfer speed using iperf utility From Server A to Server B # iperf -c 0.0.0.2 -p 8777 ------------------------------------------------------------ Client connecting to 0.0.0.2, TCP port 8777 TCP window size: 85.3 KByte (default) ------------------------------------------------------------ [ 3] local 0.0.0.1 port 38895 connected with 0.0.0.2 port 8777 [ ID] Interval Transfer Bandwidth [ 3] 0.0-10.8 sec 528 KBytes 399 Kbits/sec My Current Connections in Server B # netstat -an|grep ":8777"|awk '/tcp/ {print $6}'|sort -nr| uniq -c 2072 TIME_WAIT 28 SYN_RECV 1 LISTEN 189 LAST_ACK 139 FIN_WAIT2 373 FIN_WAIT1 3381 ESTABLISHED 34 CLOSING Server A Network Card Information Settings for eth0: Supported ports: [ TP ] Supported link modes: 100baseT/Full 1000baseT/Full 10000baseT/Full Supported pause frame use: No Supports auto-negotiation: Yes Advertised link modes: 10000baseT/Full Advertised pause frame use: No Advertised auto-negotiation: Yes Speed: 10000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 0 Transceiver: external Auto-negotiation: on MDI-X: Unknown Supports Wake-on: d Wake-on: d Current message level: 0x00000007 (7) drv probe link Link detected: yes Server B Network Card Information Settings for eth2: Supported ports: [ FIBRE ] Supported link modes: 10000baseT/Full Supported pause frame use: No Supports auto-negotiation: No Advertised link modes: 10000baseT/Full Advertised pause frame use: No Advertised auto-negotiation: No Speed: 10000Mb/s Duplex: Full Port: Direct Attach Copper PHYAD: 0 Transceiver: external Auto-negotiation: off Supports Wake-on: d Wake-on: d Current message level: 0x00000007 (7) drv probe link Link detected: yes ifconfig server A eth0 Link encap:Ethernet HWaddr 00:25:90:ED:9E:AA inet addr:0.0.0.1 Bcast:0.0.0.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:1202795665 errors:0 dropped:64334 overruns:0 frame:0 TX packets:2313161968 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:893413096188 (832.0 GiB) TX bytes:3360949570454 (3.0 TiB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:2207544 errors:0 dropped:0 overruns:0 frame:0 TX packets:2207544 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:247769175 (236.2 MiB) TX bytes:247769175 (236.2 MiB) ifconfig Server B eth2 Link encap:Ethernet HWaddr 00:25:90:82:C4:FE inet addr:0.0.0.2 Bcast:0.0.0.2 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:39973046980 errors:0 dropped:1828387600 overruns:0 frame:0 TX packets:69618752480 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3013976063688 (2.7 TiB) TX bytes:102250230803933 (92.9 TiB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:65536 Metric:1 RX packets:1049495 errors:0 dropped:0 overruns:0 frame:0 TX packets:1049495 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:129012422 (123.0 MiB) TX bytes:129012422 (123.0 MiB) Netstat -i on Server B # netstat -i Kernel Interface table Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg eth2 9000 0 42098629968 0 2131223717 0 73698797854 0 0 0 BMRU lo 65536 0 1077908 0 0 0 1077908 0 0 0 LRU I Turn up send/receive buffers on the network card to 2048 and problem still persist I increase the MTU for server A and problem still persist and i increase the MTU for server B for better connectivity and transfer speed but it couldn't transfer at all The problem is : as you can see from iperf utility, the transfer speed from server A to server B slow when i restart network service in server B the transfer in server A at full speed, after 2 minutes , it's getting slow How could i troubleshoot slow speed issue and fix it in server B ? Notice : if there any other commands i should execute in servers for more information, so it might help resolve the problem , let me know in comments

    Read the article

  • one high-end server with one Application Server or multiple Application Servers?

    - by elgcom
    If I have a high-end server, for example with 1T memory and 8x4core CPU... will it bring more performance if I run multiple App Server (on different JVM) rather than just one App Server? On App Server I will run some services (EAR whith message driven beans) which exchange message with each other. btw, has java 64bit now no memory limitation any more? http://java.sun.com/products/hotspot/whitepaper.html#64

    Read the article

  • How does Batcher Merge work at a high level?

    - by Mike
    I'm trying to grasp the concept of a Batcher Sort. However, most resources I've found online focus on proof entirely or on low-level pseudocode. Before I look at proofs, I'd like to understand how Batcher Sort works. Can someone give a high level overview of how Batcher Sort works(particularly the merge) without overly verbose pseudocode(I want to get the idea behind the Batcher Sort, not implement it)? Thanks!

    Read the article

  • PHP array help getting a value from the key

    - by sea_1987
    I have a variable that looks likes this, $rslt['expected_salary_level'] This returns a string similar to LEVEL_3, in another array that looks like this I have a set of salaries, Array ( [LEVEL_1] => Array ( [nice_name] => under &pound;10,000 [low] => 1 [high] => 10000 ) [LEVEL_2] => Array ( [nice_name] => &pound;10,000 - &pound;15,000 [low] => 10000 [high] => 15000 ) [LEVEL_3] => Array ( [nice_name] => &pound;15,000 - &pound;20,000 [low] => 15000 [high] => 20000 ) [LEVEL_4] => Array ( [nice_name] => &pound;20,000 - &pound;25,000 [low] => 20000 [high] => 25000 ) [LEVEL_5] => Array ( [nice_name] => &pound;25,000 - &pound;30,000 [low] => 25000 [high] => 30000 ) [LEVEL_6] => Array ( [nice_name] => &pound;30,000 - &pound;40,000 [low] => 30000 [high] => 40000 ) [LEVEL_7] => Array ( [nice_name] => &pound;40,000 - &pound;50,000 [low] => 40000 [high] => 50000 ) [LEVEL_8] => Array ( [nice_name] => &pound;50,000 - &pound;100,000 [low] => 50000 [high] => 100000 ) [LEVEL_9] => Array ( [nice_name] => &pound;100,000 or more [low] => 100000 [high] => 9999999 ) [LEVEL_VOLUNTARY] => Array ( [nice_name] => Voluntary [low] => [high] => ) [LEVEL_UNSPECIFIED] => Array ( [nice_name] => Not specified [low] => [high] => ) ) How do I get at the associated nice name?

    Read the article

< Previous Page | 40 41 42 43 44 45 46 47 48 49 50 51  | Next Page >