IBM's Telum II processor, detailed at Hot Chips 2024, focuses on improving performance for transactional workloads on their z16 mainframes. A key innovation is its two-level embedded DRAM (eDRAM) L4 cache. This cache operates in a unique way, acting as a victim cache for the L3 and also providing persistent storage for critical data, allowing rapid recovery after power failures. Telum II maintains the same core count and clock speeds as the original Telum but boosts memory bandwidth and capacity, significantly improving performance in transactional and general-purpose workloads. The persistent L4 also simplifies system design by absorbing some functions typically handled by firmware. The design prioritizes reliability and security, crucial for the mainframe environment.
IBM researchers have introduced Bamba, a novel open-source language model that combines the strengths of transformers and state space models (SSMs). Bamba uses a transformer architecture for its encoder and an SSM for its decoder, aiming to leverage the transformer's parallel processing for encoding and the SSM's efficient long-range dependency handling for decoding. This hybrid approach seeks to improve upon the quadratic complexity of traditional transformers, potentially enabling more efficient processing of lengthy text sequences while maintaining performance on various language tasks. Initial experiments show Bamba achieving competitive results on language modeling benchmarks and exhibiting strong performance on long-sequence tasks, suggesting a promising direction for future LLM development.
HN commenters discuss Bamba's novel approach of combining a transformer with a state space model (SSM), potentially offering advantages in handling long sequences and continuous time data. Some express skepticism about the claimed performance improvements, particularly regarding inference speed and memory usage, desiring more rigorous benchmarking against established models. Others highlight the significance of open-sourcing the model and providing training code, facilitating community exploration and validation. Several commenters note the potential applications in areas like time series analysis, robotics, and reinforcement learning, while also acknowledging the current limitations and the need for further research to fully realize the potential of this hybrid approach. A few commenters also point out the unusual name and wonder about its origin.
IBM is mandating US sales staff to relocate closer to clients and requiring cloud division employees to return to the office at least three days a week. This move aims to improve client relationships and collaboration. Concurrently, IBM is reportedly reducing its diversity, equity, and inclusion (DEI) workforce, although the company claims these are performance-based decisions and not tied to any specific program reduction. These changes come amidst IBM's ongoing efforts to streamline operations and focus on hybrid cloud and AI.
HN commenters are skeptical of IBM's rationale for the return-to-office mandate, viewing it as a cost-cutting measure disguised as a customer-centric strategy. Several suggest that IBM is struggling to compete in the cloud market and is using RTO as a way to subtly reduce headcount through attrition. The connection between location and sales performance is questioned, with some pointing out that remote work hasn't hindered sales at other tech companies. The "DEI purge" aspect is also discussed, with speculation that it's a further cost-cutting tactic or a way to eliminate dissenting voices. Some commenters with IBM experience corroborate a decline in company culture and express concern about the future of the company. Others see this as a sign of IBM's outdated thinking and predict further decline.
IBM has finalized its acquisition of HashiCorp, aiming to create a comprehensive, end-to-end hybrid cloud platform. This combination brings together IBM's existing hybrid cloud portfolio with HashiCorp's infrastructure automation tools, including Terraform, Vault, Consul, and Nomad. The goal is to provide clients with a streamlined experience for building, deploying, and managing applications across any environment, from on-premises data centers to multiple public clouds. This acquisition is intended to solidify IBM's position in the hybrid cloud market and accelerate the adoption of its hybrid cloud platform.
HN commenters are largely skeptical of IBM's ability to successfully integrate HashiCorp, citing IBM's history of failed acquisitions and expressing concern that HashiCorp's open-source ethos will be eroded. Several predict a talent exodus from HashiCorp, and some anticipate a shift towards competing products like Pulumi, Ansible, and Terraform alternatives. Others question the strategic rationale behind the acquisition, suggesting IBM overpaid and may struggle to monetize HashiCorp's offerings. The potential for increased vendor lock-in and higher prices are also raised as concerns. A few commenters express a cautious hope that IBM might surprise them, but overall sentiment is negative.
The frequently misattributed quote, "I think there is a world market for maybe five computers," is almost certainly not something Thomas Watson (Sr. or Jr.) of IBM ever said. While the exact origin remains elusive, the phrase likely emerged in the early days of computing as a reflection of the then-prevailing belief that computers were massive, expensive machines suitable only for government or large corporations. The story's persistence stems from its encapsulating the difficulty of predicting technological advancements and the dramatic evolution of computers from room-sized behemoths to ubiquitous personal devices. Various possible sources and similar quotes exist, but none definitively link the famous phrase to IBM or Watson.
Hacker News commenters discuss the often-misattributed quote about the limited market for computers. Several point out that the quote's origins are murky, with some suggesting it's a distortion of Howard Aiken's or Thomas Watson Sr.'s sentiments, while others link it to anecdotally attributed quotes in the early days of mainframe computing. Some highlight the difficulty of predicting technological adoption and the shifting definition of "computer" over time. One commenter mentions a similar misattribution regarding the market for automobiles, illustrating a broader pattern of underestimating transformative technologies. The overall sentiment reflects a shared understanding that such quotes, while entertaining, are often historically inaccurate and ultimately demonstrate the fallibility of early technological forecasting.
DOS APPEND, similar to the PATH command, allows you to specify directories where DOS should search for data files, not just executable files. This lets programs access data in various locations without needing full path specifications. It supports both drive letters and network paths, and offers options to search appended directories before the current directory or to treat appended directories as subdirectories of the current one. APPEND also provides commands to display the current appended directories and to remove them. This expands the functionality beyond the simple executable search of PATH, making data access more flexible.
Hacker News users discuss the DOS APPEND command, primarily focusing on its obscure nature and surprising functionality. Several commenters recall struggling with APPEND's unexpected behavior, particularly its ability to make files appear in directories where they don't physically exist. The discussion highlights the command's similarity to environment variables like PATH and LD_LIBRARY_PATH, with one user pointing out that it effectively extends the file search path for specific programs. Some comments mention the utility of APPEND for accessing data files across drives or directories without hardcoding paths, while others express their preference for more modern solutions. The overall sentiment suggests APPEND was a powerful but complex tool, often misunderstood and potentially problematic.
Summary of Comments ( 23 )
https://news.ycombinator.com/item?id=44028250
HN commenters discuss the complexity of the Telum II caching system, with some expressing awe at its sophistication and others questioning its necessity. Several commenters compare it to other complex caching systems, including those used in x86 and other mainframe architectures. The prevalence of Java workloads on IBM Z systems is highlighted as a potential driver for this unique caching strategy. A few commenters also delve into the specifics of the cache design, including its impact on performance and the challenges involved in managing coherence across multiple cores and L4 caches. Some skepticism is expressed about the real-world benefits of such a complex system, with some arguing that simpler designs might be equally effective.
The Hacker News post discussing the Chips and Cheese article "Telum II at Hot Chips 2024: Mainframe with a Unique Caching Strategy" has generated a moderate number of comments, primarily focusing on the technical details and implications of IBM's z16 Telum2 processor and its caching system.
Several commenters delve into the specifics of the L4 cache and its unusual implementation. One commenter highlights the innovative aspect of using DRAM for the L4, emphasizing its size and the design choices made to mitigate the inherent latency challenges associated with DRAM. They point out that the approach is essentially a hybrid between a traditional cache and main memory. This comment sparked a discussion about the trade-offs between size, speed, and cost, with other users chiming in with their perspectives on the viability and effectiveness of this approach. Some speculate about the potential influence of the CXL interconnect standard on this design.
Another thread discusses the challenges and intricacies of cache coherency in such a complex system, particularly with the introduction of the large L4. Commenters raise questions about how IBM handles the complexities of ensuring data consistency across the different levels of cache and memory. One user questions the rationale behind using DRAM for L4 instead of exploring alternative technologies like Optane or MRAM, prompting further discussion about the potential benefits and drawbacks of these technologies in this specific context.
The topic of IBM's design philosophy and their target market also emerges in the comments. Some users express admiration for IBM's continued focus on mainframe technology and their commitment to pushing the boundaries of hardware design. Others question the long-term viability of the mainframe market, wondering about the specific use cases that justify such specialized and complex systems. There's a brief exchange regarding the performance implications of the Telum2 processor for different workloads, with some commenters pointing out that while it may excel in specific scenarios, its performance advantages might not be universal.
Finally, there's a short discussion about the naming convention used by IBM, with some users expressing amusement at the "Telum" moniker and its similarity to certain culinary terms.
Overall, the comments provide a valuable technical discussion around the nuances of the Telum2 architecture, touching upon various aspects of its design and its implications for the future of mainframe computing. While not overwhelmingly numerous, the comments offer insightful perspectives from individuals with a clear understanding of computer architecture and the specific challenges faced by large-scale systems like IBM's z16 mainframe.