That's pretty much what I've been doing to get that the drive is running at 100% bandwidth.
What I'd like is something that just gives the bandwidth of the device in terms of Mb/s: you can probably work it out using that iostat command, seeing how much it wrote and what percentage of the bandwidth it's using, and then doing a calculation with those numbers to get the 100% value, but I don't know if that's valid, since there are generally a number of other operations going on at the same time. Thanks -- Ian Simpson On Fri, 2008-06-13 at 08:48 -0700, Wm Mussatto wrote: > On Fri, June 13, 2008 08:26, Ian Simpson wrote: > > Hi Jerry, > > > > It could be a kernel issue; however, currently I'm suspecting that the > > drive in the new server simply doesn't have the same bandwidth > > capability. The iostat results I'm getting (although I'm not an expert > > in reading them, having only learned of it about 3 hours ago) suggest > > that the older server is handling roughly the same data quantities, but > > just using a much lower percentage of the drive's bandwidth. > > > > I can't seem to find a tool which reports on exactly how much write > > bandwidth a drive has; everything seems to focus on reading speed. > > > > Thanks, > > > >  > > -- > > Ian Simpson > Try something like: > iostat -xk /dev/sda /dev/sdb /dev/sdc 10 > where the /dev/... are the drives you want to examine and '10' is the > redisplay rate. last column is %util. > > Hope this helps. > > > > > > > On Fri, 2008-06-13 at 11:18 -0400, Jerry Schwartz wrote: > >> >Having delved a little more into the capabilities of iostat, I've > >> >discovered that the drive bandwidth seems to be maxed out while MySQL > >> is > >> >running, which I'd peg as the primary candidate for the problem. > >> [JS] That suggests even more strongly that there is a difference in the > >> kernel > >> configuration. More physical I/O would drive the traffic up, by > >> definition. > >> Either MySQL is causing this, or the system file system is causing it. > >> > > >> >Looks like I'll be having more words with my hosting company about > >> >this... > >> > > >> >Thanks for all your help > >> >? > >> >-- > >> >Ian Simpson > >> > > >> >On Fri, 2008-06-13 at 10:40 -0400, Jerry Schwartz wrote: > >> >> >Disk usage: the older server (the one that's running fine) is > >> running > >> >> >more transactions per second, but has lower blocks written and read > >> >per > >> >> >second than the new server: > >> >> [JS] That, to me, suggests that the difference might be in the way > >> the > >> >systems > >> >> themselves are configured. Unfortunately, I don't know how Linux > >> >handles file > >> >> system buffering. > >> >> > > >> >> >The working server (which in addition to replicating is also > >> handling > >> >a > >> >> >bunch of read queries) > >> >> > > >> >> >Device: tps Blk_read/s Blk_wrtn/s Blk_read > >> >Blk_wrtn > >> >> >sda 88.47 782.20 998.77 9046888130 > >> >11551757459 > >> >> > > >> >> >The new server, which is just trying to handle replication > >> >> > > >> >> >Device: tps Blk_read/s Blk_wrtn/s Blk_read > >> >Blk_wrtn > >> >> >sda 77.83 1367.55 2914.72 358474084 > >> >764029986 > >> >> > > >> >> >Thanks, > >> >> >? > >> >> >-- > >> >> >Ian Simpson > >> >> > > >> >> > > >> >> > > >> >> >On Fri, 2008-06-13 at 19:15 +0530, Alex Arul Lurthu wrote: > >> >> >> also how often do you issue a commit. batching the inserts inside > >> a > >> >> >> transaction might help. > >> >> >> > >> >> >> On Fri, Jun 13, 2008 at 6:53 PM, Ananda Kumar <[EMAIL PROTECTED]> > >> >> >> wrote: > >> >> >> check for iostat to see if the disk is heavly used. > >> >> >> > >> >> >> > >> >> >> On 6/13/08, Ian Simpson <[EMAIL PROTECTED]> wrote: > >> >> >> Hi Alex, > >> >> >> > >> >> >> Configurations are identical, other than the > >> >> >> differences I initially > >> >> >> mentioned. I've diffed both the configuration > >> files > >> >> >> and the output of > >> >> >> SHOW VARIABLES on both servers. > >> >> >> > >> >> >> I've contacted my hosting provider to ask about > >> the > >> >> >> RAID settings. > >> >> >> > >> >> >> Variable_name: innodb_flush_log_at_trx_commit > >> >> >> Value: 1 > >> >> >> Variable_name: sync_binlog > >> >> >> Value: 0 > >> >> >> Variable_name: innodb_locks_unsafe_for_binlog > >> >> >> Value: OFF > >> >> >> > >> >> >> Thanks > >> >> >> > >> >> >> -- > >> >> >> Ian Simpson > >> >> >> > >> >> >> On Fri, 2008-06-13 at 17:43 +0530, Alex Arul > >> Lurthu > >> >> >> wrote: > >> >> >> > Please check if the my.cnf configurations to be > >> >the > >> >> >> same. > >> >> >> > > >> >> >> > What are your configuration parameters in terms > >> >of > >> >> >> innodh flush log > >> >> >> > trx commit , bin logging, sync binlog and innodb > >> >> >> unsafe for binlog ? > >> >> >> > > >> >> >> > If the systems have raid, check if the BBWC is > >> >> >> enabled on the new host > >> >> >> > and WB is enabled. > >> >> >> > > >> >> >> > > >> >> >> > On Fri, Jun 13, 2008 at 5:02 PM, Ian Simpson > >> >> >> <[EMAIL PROTECTED]> > >> >> >> > wrote: > >> >> >> > Hi list, > >> >> >> > > >> >> >> > Have a bit of a mystery here that I hope > >> >> >> somebody can help > >> >> >> > with. > >> >> >> > > >> >> >> > I've just got a new server that I'm > >> using > >> >as > >> >> >> a dedicated MySQL > >> >> >> > server. > >> >> >> > In terms of hardware it's pretty much > >> >> >> identical, if not > >> >> >> > slightly > >> >> >> > superior to an existing server already > >> in > >> >> >> production use. > >> >> >> > > >> >> >> > It's having a real struggle processing > >> >> >> INSERT statements to > >> >> >> > InnoDB > >> >> >> > tables; it's maxing out at around 100 > >> >> >> inserts per second, even > >> >> >> > with very > >> >> >> > simple two column tables (inserts into > >> >> >> MyISAM tables run > >> >> >> > fine). > >> >> >> > Meanwhile, the original server can > >> >happily > >> >> >> process around 1000 > >> >> >> > inserts/sec into an identical table. > >> >> >> > > >> >> >> > The MySQL configuration of the two > >> >databases > >> >> >> is identical, > >> >> >> > except for > >> >> >> > the tablespace file size (the new server > >> >has > >> >> >> a larger > >> >> >> > tablespace > >> >> >> > defined), and the InnoDB logs (again, > >> new > >> >> >> server has larger > >> >> >> > logs). > >> >> >> > > >> >> >> > Can anybody suggest an area of > >> >investigation > >> >> >> as to the cause? > >> >> >> > > >> >> >> > Thanks, > >> >> >> > -- > >> >> >> > Ian Simpson > >> >> >> > > >> >> >> > This email may contain confidential > >> >> >> information and is > >> >> >> > intended for the recipient(s) only. If > >> an > >> >> >> addressing or > >> >> >> > transmission error has misdirected this > >> >> >> email, please notify > >> >> >> > the author by replying to this email. If > >> >you > >> >> >> are not the > >> >> >> > intended recipient(s) disclosure, > >> >> >> distribution, copying or > >> >> >> > printing of this email is strictly > >> >> >> prohibited and you should > >> >> >> > destroy this mail. Information or > >> >opinions > >> >> >> in this message > >> >> >> > shall not be treated as neither given > >> nor > >> >> >> endorsed by the > >> >> >> > company. Neither the company nor the > >> >sender > >> >> >> accepts any > >> >> >> > responsibility for viruses or other > >> >> >> destructive elements and > >> >> >> > it is your responsibility to scan any > >> >> >> attachments. > >> >> >> > > >> >> >> > > >> >> >> > > >> >> >> > -- > >> >> >> > Thanks > >> >> >> > Alex > >> >> >> > http://alexlurthu.wordpress.com > >> >> >> > >> >> >> This email may contain confidential information > >> and > >> >is > >> >> >> intended for the recipient(s) only. If an > >> >addressing > >> >> >> or transmission error has misdirected this email, > >> >> >> please notify the author by replying to this > >> email. > >> >If > >> >> >> you are not the intended recipient(s) disclosure, > >> >> >> distribution, copying or printing of this email is > >> >> >> strictly prohibited and you should destroy this > >> >mail. > >> >> >> Information or opinions in this message shall not > >> >be > >> >> >> treated as neither given nor endorsed by the > >> >company. > >> >> >> Neither the company nor the sender accepts any > >> >> >> responsibility for viruses or other destructive > >> >> >> elements and it is your responsibility to scan any > >> >> >> attachments. > >> >> >> > >> >> >> > >> >> >> > >> >> >> > >> >> >> > >> >> >> -- > >> >> >> Thanks > >> >> >> Alex > >> >> >> http://alexlurthu.wordpress.com > >> >> > > >> >> >This email may contain confidential information and is intended for > >> >the > >> >> >recipient(s) only. If an addressing or transmission error has > >> >> >misdirected this email, please notify the author by replying to this > >> >> >email. If you are not the intended recipient(s) disclosure, > >> >> >distribution, copying or printing of this email is strictly > >> >prohibited > >> >> >and you should destroy this mail. Information or opinions in this > >> >> >message shall not be treated as neither given nor endorsed by the > >> >> >company. Neither the company nor the sender accepts any > >> >responsibility > >> >> >for viruses or other destructive elements and it is your > >> >responsibility > >> >> >to scan any attachments. > >> >> > >> >> > >> >> > >> >> > >> > > >> >This email may contain confidential information and is intended for the > >> >recipient(s) only. If an addressing or transmission error has > >> >misdirected this email, please notify the author by replying to this > >> >email. If you are not the intended recipient(s) disclosure, > >> >distribution, copying or printing of this email is strictly prohibited > >> >and you should destroy this mail. Information or opinions in this > >> >message shall not be treated as neither given nor endorsed by the > >> >company. Neither the company nor the sender accepts any responsibility > >> >for viruses or other destructive elements and it is your responsibility > >> >to scan any attachments. > >> > >> > ------ > William R. Mussatto > Systems Engineer > http://www.csz.com > 909-920-9154 > > This email may contain confidential information and is intended for the recipient(s) only. If an addressing or transmission error has misdirected this email, please notify the author by replying to this email. If you are not the intended recipient(s) disclosure, distribution, copying or printing of this email is strictly prohibited and you should destroy this mail. Information or opinions in this message shall not be treated as neither given nor endorsed by the company. Neither the company nor the sender accepts any responsibility for viruses or other destructive elements and it is your responsibility to scan any attachments.
