| # ClusterData 2011 traces |
|
|
| _John Wilkes and Charles Reiss._ |
|
|
| The `clusterdata-2011-2` trace represents 29 day's worth of Borg cell information |
| from May 2011, on a cluster of about 12.5k machines. (The `-2` refers to the fact that we added some additional data after the initial release, to create trace version 2.1.) |
|
|
| * If you haven't already joined our |
| [mailing list](https://groups.google.com/forum/#!forum/googleclusterdata-discuss), |
| please do so now. **Important**: please fill out the "reason" field, or your application will be rejected. |
| |
| ## Trace data |
|
|
| The `clusterdata-2011-2` trace starts at 19:00 EDT on Sunday May 1, 2011, and |
| the datacenter is in that timezone (US Eastern). This corresponds to a trace |
| timestamp of 600s; see the data schema documentation for why. |
|
|
| The trace is described in the trace-data |
| [v2.1 format + schema document](https://drive.google.com/file/d/0B5g07T_gRDg9Z0lsSTEtTWtpOW8/view?usp=sharing&resourcekey=0-cozD56gA4fUDdrkHnLJSrQ). |
|
|
| Priorities in this trace range from 0 to 11 inclusive; bigger numbers mean "more |
| important". 0 and 1 are “free” priorities; 9, 10, and 11 are “production” |
| priorities; and 12 is a “monitoring” priority.<br> |
|
|
| The `clusterdata-2011-2` trace is identical to the one called |
| `clusterdata-2011-1`, except for the addition of a single new column of data in |
| the `task_usage` tables. This new data is a randomly-picked 1 second sample of |
| CPU usage from within the associated 5-minute usage-reporting period for that |
| task. Using this data, it is possible to build up a stochastic model of task |
| utilization over time for long-running tasks. |
|
|
|  |
| The data and trace documentation are made available under the |
| [CC-BY](https://creativecommons.org/licenses/by/4.0/) license. |
| By downloading it or using them, you agree to the terms of this license. |
|
|
| ## Downloading the trace |
|
|
| Download instructions for the trace are in the |
| [v2.1 format + schema document](https://drive.google.com/file/d/0B5g07T_gRDg9Z0lsSTEtTWtpOW8/view?usp=sharing&resourcekey=0-cozD56gA4fUDdrkHnLJSrQ). |
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|
| The trace is stored in |
| [Google Storage for Developers](https://developers.google.com/storage/) in the |
| bucket called `clusterdata-2011-2`. The total size of the compressed trace is |
| approximately 41GB. |
|
|
| Most users should use the |
| [gsutil](https://developers.google.com/storage/docs/gsutil) command-line tool to |
| download the trace data. |
|
|
|
|
| ## Known anomalies in the trace |
|
|
| Disk-time-fraction data is only included in about the first 14 days, because of |
| a change in our monitoring system. |
|
|
| Some jobs are deliberately omitted because they ran primarily on machines not |
| included in this trace. The portion that ran on included machines amounts to |
| approximately 0.003% of the machines’ task-seconds of usage. |
|
|
| We are aware of only one example of a job that retains its job ID after being |
| stopped, reconfigured, and restarted (job number 6253771429). |
|
|
| Approximately 70 jobs (for example, job number 6377830001) have job event |
| records but no task event records. We believe that this is legitimate in a |
| majority of cases: typically because the job is started but its tasks are |
| disabled for its entire duration. |
|
|
| Approximately 0.013% of task events and 0.0008% of job events in this trace have |
| a non-empty missing info field. |
|
|
| We estimate that less than 0.05% of job and task scheduling event records are |
| missing and less than 1% of resource usage measurements are missing. |
|
|
| Some cycles per instruction (CPI) and memory accesses per instruction (MAI) |
| measurements are clearly inaccurate (for example, they are above or below the |
| range possible on the underlying micro-architectures). We believe these |
| measurements are caused by bugs in the data-capture system used, such as the |
| cycle counter and instruction counter not being read at the same time. To obtain |
| useful data from these measurements, we suggest filtering out measurements |
| representing a very small amount of CPU time and measurements with unreasonable |
| CPI and MAI values. |
|
|
| # Questions? |
|
|
| Please send email to googleclusterdata-discuss@googlegroups.com. |
|
|
