Abstract: At a data stream management service, a first set of metadata indicating that a first isolated read channel has been associated with a first data stream is stored. The first isolated read channel has an associated read performance limit setting. A second set of metadata indicating that a second isolated read channel, with its own performance limit setting, has been associated with a data stream is also stored. Based on determining that the difference between a metric of read operations associated with the first channel and the read performance limit setting of the first channel meets a first criterion, the service initiates a throttling operation for reads associated with the first channel. The throttling decision is made independently of read metrics of the second channel.

Abstract: A journal service manages a journal that holds a number of journal entries. Journal entries are provided to the journal service by one or more producer services, and the journal service provides journal entries to one or more consumer services. Lead consumers retrieve journal entries from the journal service by specifying a named cursor which identifies a location within the journal from which the journal entries are retrieved. The journal service may select a lead producer and a lead consumer from a collection of candidate producers and consumers using a fitness score determined for each candidate producer and consumer. The fitness score may be based at least in part on the processing capability, predicted reliability, and cost of each candidate producer and consumer. The journal service may replace a lead consumer or producer with an alternate consumer or producer in response to a variety of events.

Abstract: A resource manager arranges the resources in a computer system into one or more resource pools. The resource manager allocates a number of active resources and a number of backup resources to a particular resource pool. For each resource managed by the resource manager, the resource manager acquires information that describes the capacity and reliability of the resource. Capacity and reliability information for the particular resource pool is determined based on the capacity and reliability information associated with the resources assigned to the pool. In response to a request, the resource manager may provide an application with resources from several resource pools. The likelihood that the resource manager will be able to provide sufficient resources to the application may be determined based at least in part on the reliability information associated with the several resource pools.

Abstract: A pipeline management service improves the operation of a processing pipeline by monitoring the operation of one or more journal services within the processing pipeline, and adjusting operational parameters of the one or more journal services. In various examples, the pipeline management service determines a model of the processing pipeline by identifying the producers and consumers associated with each of the one or more journal services, and determines a processing flow through the one or more journal services based at least in part on the identities of the associated producers and consumers. The pipeline management service acquires backlog information from each of the one or more journal services, and may adjust the operational parameters of a journal service associated with an identified processing bottleneck. In some examples, the pipeline management service adjusts capacity and reliability parameters of the one or more journal services to improve the operation of the processing pipeline.

Abstract: The preemption of running jobs by other running or queued jobs in a system that has processing resources. The system has running jobs, and queued jobs that are awaiting processing by the system. In a scheduling operation, preemptor jobs are identified, the preemptor jobs being jobs that are candidates for preempting one or more of the running jobs. The preemptor jobs include queued jobs, as well as running jobs that are capable of using more processing resource of the system. One of the other running jobs is preempted to free processing resources for the running job that was identified as a preemptor job. Accordingly, not only may queued jobs preempt running jobs, but currently running jobs may preempt other currently running jobs.

Abstract: A scheduler for a compute cluster that allocates computing resources to jobs to achieve a balanced distribution. The balanced distribution maximizes the number of executing jobs to provide fast response times for all jobs by, to the extent possible, assigning a designated minimum for each job. If necessary to achieve this minimum distribution, resources in excess of a minimum previously allocated to a job may be de-allocated, if those resources can be used to meet the minimum requirements of other jobs. Resources above those used to meet the minimum requirements of executing jobs are allocated based on a computed desired allocation, which may be developed based on respective job priorities. To meet the desired allocation, resources may be de-allocated from jobs having more than their desired allocation and re-allocated to jobs having less than their desired allocation of resources.

Abstract: The scheduling of a processing job to be performed by at least a portion of a cluster of processing resources distributed across multiple machines. The processing job is associated with a certain entity having a certain amount of guaranteed processing resources on the cluster. If there are enough processing resources to perform the job, then the job may be initiated. On the other hand, if there are not enough processing resources to perform the job, and there are yet some remaining processing resources that are guaranteed to the certain entity, then one or more other jobs that are associated with other entities are at least partially preempted until there are enough processing resources to perform the processing job.

Abstract: The preemption of running jobs by other running or queued jobs in a system that has processing resources. The system has running jobs, and queued jobs that are awaiting processing by the system. In a scheduling operation, preemptor jobs are identified, the preemptor jobs being jobs that are candidates for preempting one or more of the running jobs. The preemptor jobs include queued jobs, as well as running jobs that are capable of using more processing resource of the system. One of the other running jobs is preempted to free processing resources for the running job that was identified as a preemptor job. Accordingly, not only may queued jobs preempt running jobs, but currently running jobs may preempt other currently running jobs.

Abstract: The scheduling of a processing job to be performed by at least a portion of a cluster of processing resources distributed across multiple machines. The processing job is associated with a certain entity having a certain amount of guaranteed processing resources on the cluster. If there are enough processing resources to perform the job, then the job may be initiated. On the other hand, if there are not enough processing resources to perform the job, and there are yet some remaining processing resources that are guaranteed to the certain entity, then one or more other jobs that are associated with other entities are at least partially preempted until there are enough processing resources to perform the processing job.

Abstract: A command to perform a task can be received and the task can be started. A command to cancel the task can also be received. The task can be provided with a warning signal and a predetermined grace period of time before cancelling the task, which can allow the task to prepare for cancellation, such as by shutting down cleanly. If the task has not shut down within the grace period, then the task can be cancelled after the grace period expires.

Abstract: A scheduler for a compute cluster that allocates computing resources to jobs to achieve a balanced distribution. The balanced distribution maximizes the number of executing jobs to provide fast response times for all jobs by, to the extent possible, assigning a designated minimum for each job. If necessary to achieve this minimum distribution, resources in excess of a minimum previously allocated to a job may be de-allocated, if those resources can be used to meet the minimum requirements of other jobs. Resources above those used to meet the minimum requirements of executing jobs are allocated based on a computed desired allocation, which may be developed based on respective job priorities. To meet the desired allocation, resources may be de-allocated from jobs having more than their desired allocation and re-allocated to jobs having less than their desired allocation of resources.