Berkeley CSUA MOTD:Entry 35112
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2025/05/25 [General] UID:1000 Activity:popular
5/25    

2004/11/29-30 [Computer/HW/Drives] UID:35112 Activity:moderate 66%like:35109
11/29   So what is TDA?  Why does it keep bringing soda down?
        \_ http://now.cs.berkeley.edu/Td
           The TDA is filled with nice, old, slow 8GB disks.  The TDA isn't
           bringing soda down, soda is bringing soda down.  The issue with the
           TDA is that the hardware itself is not very reliable.  If it turns
           off, there is no guarantee that it will spin back up again,
           resulting in a catastrophic loss of the motd (well actually, I think
           the motd is on an internal disk, but without your home directories
           you may have a small issue actually logging in).  In short, TDA
           sucks and we're getting off of it. - jvarga
           \_ ^TDA^Yermom
           \_ Has screwdriver experienced issues with TDA?
              \_ Screwdriver is running fibre channel disk, not TDA.
                 \_ Hail the Glorious new revolution!
        \_ It's a trinary digital assistant, 50% more powerful than a regular
           PDA.
        \_ Someone replied before and said it was a terabyte disk array.  Is
           that true?  If so, why do we still have measly 30 MB quotas?
           \_ As I replied to that thread, no, it stands for tertiary disk
              array.  -- njh
           \_ Because 8GB disks * 4 disks = 32GB of fun for all ~2500
              hozers.  Type `df` and look at /home/* to see why you don't
              have huge quotas.  There *are* quota upgrades coming with
              new soda, so donate well! - jvarga
              \_ I don't think I've ever seen an official upgrade proposal or
                 a request for donation.  Do you have a pointer to either?
                 \_ I could have sworn there was an official posting on
                    this... I'll look around or post again.  Soda is gettin
                    some dual P4 Xeon luvin (I have yet to figure out how to
                    get them to burn a hole in the machine room wall, but I am
                    definitely trying).  Ooodles of disk space and RAM come
                    with it too.  Depending on how our finances look (ASUCk
                    money, donations, etc), we are seriously considering
                    offloading mail handling to another machine (and putting
                    virus scanning into the mix to kill off some of that
                    pesky virus-laden mail).  We are also looking to give some
                    of the other servers face lifts (upgrades to somewhat
                    modern technology like motherboards without ISA slots like
                    a high-end PIII or something cheap).
                    Everyone will be getting some quota love... maybe up to
                    100-150MB (don't quote me on this, it isn't set in stone
                    yet because we don't know how much disk we can buy or
                    even what is considered reasonable).
                    I'd love to give official specs on what we are planning,
                    but those are changing because of finances. - jvarga
                    \_ I think everyone else on the motd has asked already,
                       but why dual Xeons?  It's a fine choice, apart from
                       the fact that it runs warmer, slower, and is more
                       expensive.
                       \_ We've all asked and have never been given an answer.
                          I think they pulled the choice out of their spleen
                          and have no satisfactory reason.
           \_ Uh, because it DOESN'T WORK and CRASHES SODA
              \_ Maybe that's because it was never designed to work with vinum.
                 \_ Are you talking straight out of your ass, or is it taking
                    a detour through your spleen?
           \_ wc /etc/passwd
              2906    6617  203836 /etc/passwd
              \_ we should each get at some where around 300MB.
              \_ Sure, if you can make 4 8GB disks add up to 1TB.
           \_ So what's causing the instability? RAID driver?  Hardware?
              \_ ilyas
                 \_ I may destabilize soda for generations to come. -- ilyas
                    \_ Nah, you'll go back on your medication eventually
                       \_ What's with all the hatin' on ilyas?  Isn't tom still
                          around and a good target for kicking?
              \_ Soda has just been crashing itself lately...no real idea why.
                 The resent *planned* shutdowns were to put bigger disk online.
                 \_ I believe that at a politburo meeting the politburo was
                    told exactly why it was crashing, from people who went thru
                    the crash dumps.  Basically, the OS is too old/broken.
                    \_ Well, yes, the OS is old and crufty, but that doesn't
                       explain why soda has been crashing.  And yes, I have
                       been going through the crash dumps --njh
         \_ We should just replace the whole thing with a cheapo terrabyte
            IDE raid on a P4 3 gig or AMD equivalent. I built one for about
            $2500. We could each donate like $100 or more and get it done.
            -williamc
            \_ Set up the paypal account, and I'll cough up a twenty.
               \_ There has been a paypal link on the csua web page for at
                  least a month now.
               \_ But what if williamc collects all the money and then escapes
                  into South America?
               \_ I'd like to know what the Politburo plans to do before I
                  cough up the dough.
                  \_ See above
        \_ TDA...Totally Dumb Acronym.
2025/05/25 [General] UID:1000 Activity:popular
5/25    

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2011/9/14-10/25 [Computer/HW/Drives] UID:54173 Activity:nil
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2011/2/14-4/20 [Computer/SW/Unix] UID:54039 Activity:nil
2/14    You sure soda isn't running windows in disguise?  It would explain the
        uptimes.
        \_ hardly, My winbox stays up longer.
        \_ Nobody cares about uptime anymore brother, that's what web2.0 has
           taught us.  Everything is "stateless".
           \_ You;d think gamers would care more about uptime.
	...
2011/2/18-4/20 [Computer/SW/Unix] UID:54044 Activity:nil
2/18    Why does the system seem so sluggish lately?
        \_ Slow NFS is basically always the answer. --toulouse
        \_ Any truth to the rumor that soda will be decommissioned this summer?
           \_ Absolutely none. Soda might go down temporarily while disks are
              reorganized and stuff so soda doesn't suffer from such shitty
              performance nearly as much, but no, we've gotta maintain NFS and
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        \_ thinkpad t23 w ssdrive and battery inplace of drive bay
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2009/10/27-11/3 [Computer/HW/Drives] UID:53474 Activity:nil
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        \_ I hope you're not running mission critical data:
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        \_ Do you have any idea how much storage space is used by Facebook,
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Cache (2457 bytes)
now.cs.berkeley.edu/Td -> now.cs.berkeley.edu/Td/
In the past 5 years, the cost performance gap between secondary and terti ary storage has been widening. The cost per megabyte of disk drives has been falling at a factor of 2 per year, compared to 15 per year for tap e drives and libraries. Disk areal densities have been increasing at 60% per year, with 8 GB 35 inch disk units currently available. Data rates have also been increasing at rates of 40% per year, expected to pass 40 MB/s by the end of the decade. These trends change the possibilities in large scale storage systems. If they continue, large storage systems co mposed of disks will have significant cost/performance advantages over t ape libraries of similar capacity. Applications such as databases, video on demand, medical data and web arc hival have a need for storage systems which are high performance as well as high capacity. The solution used in most cases is a hierarchy of a d isk array and tape library. However, disk arrays have drawbacks in terms of cost/performance, availability, and scalability. Due to custom hardw are, the cost per megabyte of RAID disk arrays increases with system cap acity, unlike raw disks and tape systems. Also, a disk array needs to be connected to a host computer, which becomes a bottleneck for both perfo rmance and availability. Its scalability is limited by the number of dis ks that can be supported by the infrastructure. Some storage consuming a pplications like web archival have a fixed growth rate of data. When suc h applications reach the capacity limit of their disk array, another arr ay must be added. Adding independent disk arrays also lowers the reliabi lity of the total system and complicates storage management. Tertiary Disk is a storage system architecture which exploits the trends mentioned above to create large disk storage systems that avoid the disa dvantages of custom built disk arrays. The name comes from twin goals: t o have the cost per megabyte and capacity of tape libraries and the perf ormance of magnetic disks. We use commodity, off the shelf components to develop a scalable, low cost, terabyte capacity disk system. Our target is to build a complete storage system with about 30-50% extra to the co st of the raw disk. Tertiary Disk uses PCs connected by a switched netwo rk to host a large number of disks. Our prototype consists of 20 200MHz PC PCs, which host 370 8GB disks. The PCs, running FreeBSD, are connecte d through a 100Mbps Ethernet switch.